Best Filament for the Original Prusa MK3S and MK3S+ (2026)

Quick picks

These are defaults by need, not a ranking.

Who this page is for

This page is for owners of an Original Prusa i3 MK3S or MK3S+ who want to know which spools suit their printer before buying. Prusa describes the MK3S+ as an MK3S with a new SuperPINDA probe, better bearings and "various useful design tweaks." The specifications we use come from Prusa's MK3S+ 10th Anniversary Edition product page, so the limits below are Prusa's figures for the MK3S+. If you own a newer MK4S or CORE One, see the CORE One and MK4S filament page instead. For upgrades with a documented fit, see the MK3S printer page.

The table is grouped by job, not ranked.

What can the MK3S and MK3S+ print, per Prusa?

Limits. The specifications on Prusa's MK3S+ 10th Anniversary Edition product page list a 300 °C maximum nozzle temperature, a 120 °C maximum heatbed temperature, 1.75 mm filament and a 0.4 mm default nozzle. The handbook's safety notes give the nozzle temperature as "210-300 °C," and it says "This printer supports only a 1.75 mm filament." One caveat: the comparison table on the same Prusa product page lists "290 °C / 120 °C" for the MK3S+. Every spool on this page stays at 270 °C or below, so the difference doesn't affect these picks.

Extruder and hotend. Prusa lists the extruder as "Direct Drive, Bondtech gears, V6 hotend." For the MK3S+, it says "the filament path in the extruder was altered for better support of flexible filaments." The comparison table on the same page lists the MK3S+ as direct drive and the MINI+ as a Bowden system.

Materials. Prusa's MK3S+ page lists a "wide range of thermoplastics, including PLA, PETG, ASA, ABS, PC (Polycarbonate), CPE, PVA/BVOH, PVB, HIPS, PP (Polypropylene), Flex, nGen, Nylon, Carbon filled, Woodfill and other filled materials." That list covers what the hardware can reach. Prusa's material guides add conditions for several of them, covered below.

Enclosure. Prusa's MK3S+ specifications don't list an enclosure. Prusa sells the Original Prusa Enclosure as a separate accessory, and its product page, now titled "Original Prusa MK4/S Enclosure," says it "houses your Original Prusa i3 MK3S+ or MK4." That page doesn't name the original MK3S. Prusa says the enclosure is heated passively by the heatbed, and it offers an optional HEPA filter.

Heat in use. Prusa's PLA guide says PLA "gets soft and deforms at temperatures over 60 °C." Its PETG guide calls PETG suitable for interior and most exterior use "with temperatures below 80 °C." For hotter or outdoor parts, ASA is the better fit, in an enclosure. Our PLA vs ASA guide covers that trade-off.

Nozzles: what fits and when brass isn't enough

Prusa's E3D V6 nozzle article says "The E3D (or E3D compatible) V6 nozzles fit into the MK3, MK3S, MK3S+," as well as earlier models and the MINI/+. That's Prusa's general statement, and it doesn't name any third-party brand. The article also says the MK3S+ ships with E3D 0.4 mm nozzles. Prusa's handbook says it supports E3D's 0.8, 0.6, 0.25 and hardened steel nozzles, and it also describes the Olsson Ruby for highly abrasive materials.

The same article says "The Prusa FFF printers are equipped with a brass nozzle," and that a brass nozzle "will degrade quickly" with abrasive filaments. Our worn nozzle guide covers the signs. Prusa says most abrasive materials are composites and plastics with additives, naming Bronzefill, Brassfill, filaments with carbon compound, and some glow-in-the-dark filaments. Its nozzle-size table marks wood- or metal-infused filaments and CF- or Kevlar-infused ABS as needing a hardened nozzle at 0.4 mm. Prusa says you may need to "increase the hotend temperature by about 5°C" with a hardened steel nozzle. Our abrasive filament nozzle guide covers the options.

MMU2S and MMU3 notes

Prusa's MMU3 compatibility article says the MMU3 is compatible with the MK3S+, and "All the required parts are included in the MMU3 MK3S+ package." On an original MK3S, Prusa says the combination "is possible," but the MMU3 package has extruder parts designed for the MK3S+ extruder only. Prusa says "Upgrading to MK3S+ is recommended before attaching the MMU3." An MMU2S running firmware 3.0.0 or later is listed as compatible with both.

Prusa's nozzle article adds that for the MMU2S, "we only provide presets for a 0.25 mm, 0.4 mm, or 0.6 mm brass nozzle," and that hardened steel or other alloys "may cause issues." So if you print with an MMU, plan on staying with brass and leaving abrasive spools out of it. The TPU printing tips on Overture's TPU 95A page say TPU is "Not compatible with AMS or other multi-material systems."

Everyday PLA

PLA is the easiest material on an MK3S. Prusa's handbook says "your first filament should definitely be PLA." Prusa's PLA guide says the satin or smooth PEI sheet "will provide the best adhesion."

Prusament PLA (Jet Black, 1 kg)

Prusament is Prusa's own filament brand, which makes it a straightforward choice on a Prusa printer. Prusa's material page lists a 210 ± 10 °C nozzle, a 40–60 °C bed, "Enclosure not required," and a temperature resistance of 55 °C. It also lists low UV resistance and says it's "not ideal for outdoor use." Prusa lists "Low warping" among its pros and "Brittle" among its cons.

Prusa Research

Prusa Research Prusament PLA (Jet Black, 1.75 mm, 1 kg)

Best for

Precise everyday PLA prints, especially on Prusa printers with stock profiles.

Skip this if

The part needs heat, UV, or mechanical-stress resistance.

Specs, strengths, and limitations

Material

PLA

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

plastic spool

Maker's nozzle range

200–220 °C

Strengths

• Manufacturer states diameter precision of ±0.02 mm and publishes measured data for every spool.
• Manufacturer states low warping, suitable for large prints.
• Manufacturer states guaranteed color consistency between batches.

Limitations

• Not suited to heat or outdoor use: Prusa lists 55 °C temperature resistance and low UV resistance.
• Prusa suggests PETG or PC Blend for mechanically stressed parts, and lists PLA as difficult to sand.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if the part will see heat, sun or repeated bending.

Polymaker PolyLite PLA (Black, 1 kg)

PolyLite PLA is a non-Prusament alternative that, like Prusament, needs no enclosure on an MK3S. Its TDS (V5.4) lists a 190–230 °C nozzle, a 25–60 °C bed, "Closure Chamber: No Needed," and a heat deflection temperature of 58 °C at 1.8 MPa. It ships on a cardboard spool.

Polymaker

Polymaker PolyLite PLA (Black, 1.75 mm, 1 kg)

Best for

Everyday PLA prints, prototypes, and display models where a documented, easy-printing PLA is wanted.

Skip this if

The part will sit in a hot car, near heat sources, or needs toughness beyond standard PLA.

Specs, strengths, and limitations

Material

PLA

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

190–230 °C

Strengths

• Manufacturer states PolyLite PLA is designed for reliability and ease of printing.
• Manufacturer TDS lists no enclosure needed and a wide 190–230 °C nozzle window.
• Manufacturer publishes a full TDS with mechanical, thermal, and drying data.

Limitations

• Not suited to parts exposed to heat: the TDS lists a heat deflection temperature of 58 °C (1.8 MPa).
• Cardboard spool: Polymaker says its spools have hardened edges that work in the AMS, but Bambu Lab's general AMS guidance recommends an adapter or ring for cardboard spools. Check your unit.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if the part will see heat, or you'd rather stay with Prusa's own filament.

Polymaker PolyLite PLA Pro (Black, 1 kg)

PolyLite PLA Pro is Polymaker's toughened PLA, for household parts and prototypes that may get dropped. Its TDS lists the same 190–230 °C nozzle range, a 30–60 °C bed, no closed chamber needed, and a heat deflection temperature of 58 °C at 1.8 MPa. So it still has PLA's heat limit.

Polymaker

Polymaker PolyLite PLA Pro (Black, 1.75 mm, 1 kg)

Best for

Functional PLA parts, props, and prototypes that need more drop resistance than standard PLA.

Skip this if

The part will see heat above about 55 °C (TDS HDT 58 °C at 1.8 MPa) or needs to flex.

Specs, strengths, and limitations

Material

PLA (PLA Pro (toughened PLA))

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

190–230 °C

Strengths

• Manufacturer states it combines high toughness and high rigidity with the ease of printing of regular PLA.
• TDS lists notched Charpy impact strength of 17.1 kJ/m² (X-Y).
• Manufacturer publishes a full TDS with mechanical, thermal, and drying data.

Limitations

• Not for heat: the TDS lists a heat deflection temperature of 58 °C (1.8 MPa), and Polymaker says it is not for projects needing high heat resistance or flexibility.
• Cardboard spool: Bambu Lab strongly advises a spool adapter or adapter ring for cardboard spools in the AMS.
• Polymaker now calls this the 'Old Formula' and sells a separate 'New Formula' Polymaker PLA Pro; check which version an Amazon listing ships.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if the part will sit somewhere warm or needs to flex.

PETG for functional parts

Prusa says it prints parts for its printers from PETG. Its PETG guide warns, "Do not print on the smooth PEI sheet as the adhesion may be too strong!" It recommends a powder-coated or satin sheet, or glue stick if you must use smooth PEI. That applies to every PETG below. For the trade-offs between the two materials, see our PLA vs PETG guide.

Prusament PETG (Jet Black, 1 kg)

Prusament PETG is Prusa's own PETG. Its TDS lists a 250 ± 10 °C nozzle and an 80 ± 10 °C heatbed, with satin, powder-coated or smooth PEI (with glue stick) sheets. It gives a heat deflection temperature of 68 °C. Prusa's material page warns of "Strong adhesion to the bed - be careful when you're removing the print," and lists possible stringing as a con.

Prusa Research

Prusa Research Prusament PETG (Jet Black, 1.75 mm, 1 kg)

Best for

Functional parts, brackets, and larger prints that need more toughness than PLA.

Skip this if

The part needs heat resistance above about 68 °C (TDS HDT at 0.45 and 1.8 MPa), or you want a matte finish that hides layer lines.

Specs, strengths, and limitations

Material

PETG

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

plastic spool

Maker's nozzle range

240–260 °C

Strengths

• Manufacturer states high strength and durability with low shrinking and warping.
• Manufacturer states diameter precision of ±0.02 mm and publishes measured data for every spool.
• Manufacturer states it is easier to sand than PLA.

Limitations

• Prusa lists possible stringing that may require occasional drying, and poor bridging.
• Strong bed adhesion: Prusa warns to take care removing prints, recommends textured, satin or PP sheets, and says to avoid smooth PEI (glue stick if used).
• Heat resistance tops out around 68 °C: the TDS gives HDT 68 °C at both 0.45 and 1.8 MPa.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if the part needs more heat resistance than PETG offers.

Polymaker PETG (Black, 1 kg)

Polymaker's current PETG is a high-flow formula. Its TDS (V3.0) lists a 240–260 °C nozzle, a 60–70 °C bed and "Closure chamber: Not Needed." It recommends drying at 60 °C for 6 hours. It ships on a cardboard spool.

Polymaker

Polymaker PETG (Black, 1.75 mm, 1 kg (new formula))

Best for

Functional brackets and fixtures, indoors or in shade, that need more toughness than PLA.

Skip this if

You can't keep filament dry, or the part needs heat resistance well above 65 °C (TDS HDT at 1.8 MPa).

Specs, strengths, and limitations

Material

PETG (high-flow)

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

240–260 °C

Strengths

• Manufacturer states it is less brittle and more impact-resistant than PLA.
• Manufacturer states it prints without an enclosure and works with AMS and multi-material systems.
• Manufacturer states a high-flow formulation for speeds up to 300 mm/s with a 0.4 mm nozzle.

Limitations

• Moisture-sensitive: the TDS recommends drying at 60 °C for 6 h and printing from a dry box.
• Heat resistance is limited: the TDS lists HDT 65 °C at 1.8 MPa (69 °C at 0.45 MPa).
• Cardboard spool: Polymaker says its spools have hardened edges that work in the AMS, but Bambu Lab's general AMS guidance recommends an adapter or ring for cardboard spools. Check your unit.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if you can't keep filament dry.

eSUN PETG (Solid Black, 1 kg)

eSUN PETG is a PETG from a maker that publishes a dated data sheet. Its TDS (V2.0) lists a 230–260 °C nozzle, a 75–90 °C build platform and UV resistance. It recommends drying at 60 °C for more than 8 hours. eSUN's TDS gives a heat distortion temperature of 64 °C at 0.45 MPa.

eSUN

eSUN PETG (Solid Black, 1.75 mm, 1 kg)

Best for

Everyday PETG for outdoor and functional parts from a long-established brand.

Skip this if

Your bed can't reach 75 °C or the part needs heat resistance above about 60 °C (TDS heat distortion temperature 64 °C at 0.45 MPa).

Specs, strengths, and limitations

Material

PETG

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

other

Maker's nozzle range

230–260 °C

Strengths

• Manufacturer states it combines PLA's easy printing with ABS's toughness.
• Manufacturer TDS lists UV resistance, and the product page states it withstands sun and rain outdoors.
• Manufacturer publishes a dated TDS with print and drying settings.

Limitations

• Needs a hot bed: the TDS lists 75–90 °C build platform temperature.
• Heat resistance is limited: the TDS lists a heat distortion temperature of 64 °C (0.45 MPa).
• eSUN's own guidance varies between its TDS and product page (nozzle 230 vs 240 °C start).

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if the part will run hot.

TPU for flexible parts

Prusa lists Flex for the MK3S+. Its handbook says to clean the nozzle of the previous material first, and "When inserting Flex, loosen the pressure on the idler as much as possible." Prusa's flexible materials guide says "the softer the filament is, the harder it is to print." It gives a typical speed of 20 mm/s and a maximum "somewhere between 30 and 40 mm/s," and says to keep flexible filament dry. Both spools below are 95A, the firmer end of common TPU, and both makers name direct drive or slow printing in their own guidance. Our TPU compatibility guide explains hardness grades.

Polymaker PolyFlex TPU95 (Black, 0.75 kg)

PolyFlex TPU95's TDS (V5.4) lists Shore 95A, a 210–230 °C nozzle, a 25–60 °C bed, no closed chamber needed, and drying at 70 °C for 8 hours. Polymaker's product page says, "We highly recommend to use a direct drive printer to print PolyFlex™ TPU95," which the MK3S is. The page's print settings give 20–40 mm/s. The spool holds 0.75 kg on cardboard.

Polymaker

Polymaker PolyFlex TPU95 (Black, 1.75 mm, 0.75 kg)

Best for

Flexible covers, grips, bumpers, and seals on printers that handle 95A TPU.

Skip this if

You need a softer TPU than 95A, or fast print times, or your printer is set up as Bowden and you can't print very slowly (Polymaker highly recommends direct drive and says Bowden is possible only at very slow speeds).

Specs, strengths, and limitations

Material

TPU

Diameter

1.75 mm

Net filament

750 g (filament only, not packaged weight)

Hardness

95A

Format

cardboard spool

Maker's nozzle range

210–230 °C

Strengths

• Manufacturer states it is engineered to work on most desktop 3D printers without specialized hardware.
• Manufacturer states it can stretch over three times its original length.
• Manufacturer TDS lists shore hardness 95A and no enclosure needed.

Limitations

• Slow printing: the TDS recommends 30–50 mm/s.
• Spool holds 0.75 kg, not 1 kg.
• Cardboard spool: Polymaker says it redesigned its spool edges to spin well in the AMS, but its Flexible TPU FAQ says TPU is often too soft to feed through the AMS and suggests avoiding it. Bambu Lab also advises against TPU in the AMS and recommends an adapter or ring for cardboard spools.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if you want a 1 kg spool or a softer TPU.

Overture TPU 95A (Black, 1 kg)

Overture's product page lists 95A hardness, a 210–240 °C nozzle and a 35–50 °C bed. Its spec table lists a printing speed under 250 mm/s, but the TPU printing tips on the same page recommend 20–40 mm/s with retraction off or minimal. The page gives drying at 70 °C for 7 hours and warns that drying too long can make it brittle. The TPU 2.0 data sheet linked from the page gives a wider 25–60 °C bed range and 8 hours of drying, so Overture's own documents differ. The same printing tips say TPU is "Not compatible with AMS or other multi-material systems."

Overture

Overture TPU 95A (Black, 1.75 mm, 1 kg)

Best for

General-purpose 95A flexible parts such as gaskets, seals, and protective cases.

Skip this if

You plan to feed it through a Bambu Lab AMS or AMS lite, or you want a TPU whose maker recommends it for Bowden printers.

Specs, strengths, and limitations

Material

TPU

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Hardness

95A

Format

cardboard spool

Maker's nozzle range

210–240 °C

Strengths

• Manufacturer states its 95A Shore hardness balances softness and toughness for impact absorption and rebound.
• Manufacturer states it resists oil and recovers its shape after repeated stress.
• Manufacturer states unopened spools have a 1-year shelf life with proper storage.

Limitations

• The TPU printing tips on Overture's product page say 'Not compatible with AMS or other multi-material systems.'
• Overture marks it 'AMS & AMS lite NOT Compatible', and its FAQ says TPU is too soft for the AMS and can jam or extrude inconsistently.
• Overture's own documents disagree on bed temperature, drying time, and elongation (see notes).
• Manufacturer says to keep it dry before use.
• Overture's TPU wiki says to use a direct-drive system or an external extruder attachment, and its extruder wiki rates Bowden support for flexible filament as 'Limited'; the product page doesn't mention Bowden.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if you print through an MMU, or want one consistent set of maker settings.

Does the MK3S need an enclosure for ASA and ABS?

Prusa's ASA guide says "the bed should be heated to at least 100 °C, and the printer should be inside an enclosure to keep a higher ambient temperature." It recommends 105 °C for the first layer and 110 °C after that, within the MK3S+'s 120 °C bed limit. Prusa's ABS guide lists "Requires printer enclosure" as a disadvantage. Both guides say to print "in a well-ventilated room because the material releases fumes and substances that could pose a potential health risk."

Without an enclosure, both guides suggest PrusaSlicer's draft shield option as "one simple alternative." Both also warn that printing inside an enclosure can deform the fan shroud and other plastic parts. The ASA guide says this can happen over time when you print a lot of ASA in an unventilated enclosure. Prusa's enclosure page names the MK3S+. Our catalog has no third-party enclosure with a recorded MK3S or MK3S+ fit. 3D Sourcerer says its DELACK kit is designed for the "Prusa MK3 series," but it doesn't name the MK3S or MK3S+, and the kit leaves out the 3D-printed parts. Check fit with the maker before buying a third-party enclosure. Our ABS vs ASA guide, enclosure planning guide and printer enclosures shortlist cover the choice.

Prusament ASA (Natural, 800 g)

Prusa's material page lists a 260 ± 5 °C nozzle, a 110 ± 5 °C bed and "Skirt or Enclosure Recommended." Its TDS (v1.1) gives a wider 260 ± 10 °C nozzle range and the same bed range, so both fit the MK3S+'s limits. Prusa calls the material "UV stable" and says it shows "no signs of deformation up to temperatures near 93 °C." It also says the "fan-shroud on Original Prusa i3 MK3S is newly made of ASA material." Prusa recommends the satin sheet and warns that adhesion to the powder-coated or smooth sheet "can be too strong." The spool holds 800 g, and it's sold in Natural rather than black.

Prusament

Prusament ASA (Natural, 1.75 mm, 800 g)

Best for

Prusa owners and anyone who wants a thoroughly documented, UV-stable ASA for outdoor parts.

Skip this if

Your bed can't reach 110 °C or you print in an unventilated room.

Specs, strengths, and limitations

Material

ASA

Diameter

1.75 mm

Net filament

800 g (filament only, not packaged weight)

Format

other

Maker's nozzle range

250–270 °C

Strengths

• Manufacturer states ASA is UV stable and shows no deformation up to about 93 °C.
• Prusa publishes a full TDS and measures diameter along every spool.
• Manufacturer states it can be smoothed with acetone vapor and sanded wet or dry.

Limitations

• Spool holds 800 g, less than the 1 kg spools here.
• Needs a 110 °C bed, and Prusa recommends an enclosure or tall skirt to control warping.
• Prusa warns of styrene fumes and recommends ventilation or an enclosure with active filtration.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-07 against the manufacturer. Price and availability are on Amazon.

Skip it if your MK3S isn't enclosed, or you want a 1 kg spool.

Polymaker ASA (Black, 1 kg)

Polymaker's ASA TDS (V6.0) lists a 230–260 °C nozzle, a 75–95 °C bed, "Closure chamber: Needed," and a heat deflection temperature of 100 °C at 1.8 MPa. It recommends drying at 70 °C for 7 hours. Its bed range is lower than Prusa's ASA guide suggests, so start with Polymaker's own settings. It ships on a cardboard spool. For the wider ASA picture, see the ASA filament shortlist.

Polymaker

Polymaker ASA (Black, 1.75 mm, 1 kg)

Best for

Outdoor and sun-exposed functional parts printed on an enclosed machine.

Skip this if

Your printer is open-frame or can't reach a 95 °C bed and 260 °C nozzle.

Specs, strengths, and limitations

Material

ASA

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

230–260 °C

Strengths

• Manufacturer states it is an alternative to ABS with improved weather and UV resistance.
• Manufacturer TDS lists a heat deflection temperature of 100 °C (1.8 MPa).
• Manufacturer states it prints with settings very similar to ABS.

Limitations

• Needs an enclosed printer per the TDS.
• Requires higher nozzle and bed temperatures (230–260 °C, 75–95 °C) than PLA or PETG.
• Cardboard spool: Bambu Lab strongly advises a spool adapter or adapter ring for cardboard spools in the AMS.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if your MK3S isn't enclosed.

Polymaker PolyLite ABS (Black, 1 kg)

Polymaker's PolyLite ABS data sheet (V5.5) lists a 245–265 °C nozzle, a 90–100 °C bed, the cooling fan off and a closed chamber as "Needed." The TDS lists a heat deflection temperature of 98 °C at 1.8 MPa and drying at 70 °C for 6 hours. Prusa's ABS guide notes that ABS lacks ASA's UV resistance. It ships on a cardboard spool.

Polymaker

Polymaker PolyLite ABS (Black, 1.75 mm, 1 kg)

Best for

Heat-resistant functional parts, enclosures, and prototypes printed on an enclosed printer.

Skip this if

Your printer is open-frame or its bed can't reach 90 °C.

Specs, strengths, and limitations

Material

ABS

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

245–265 °C

Strengths

• Manufacturer states PolyLite ABS uses a bulk-polymerized ABS resin with significantly lower volatile content than traditional ABS, for minimal odor.
• TDS lists a heat deflection temperature of 98 °C at 1.8 MPa.
• Manufacturer publishes a full TDS with mechanical, thermal, and drying data.

Limitations

• TDS lists a closed chamber as 'Needed'. Polymaker's product page says a non-enclosed printer with a 90 °C bed and 260 °C nozzle can handle models smaller than fist size, larger prints need an enclosed printer (about 40–50 °C), and models over about 15–20 cm need a heated chamber (about 70 °C or more).
• Needs a 90–100 °C bed (TDS), so printers with low-temperature beds aren't suitable.
• Cardboard spool: Bambu Lab strongly advises a spool adapter or adapter ring for cardboard spools in the AMS.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if your MK3S isn't enclosed, you can't ventilate the room, or the part will live outdoors.

Can the MK3S print carbon fiber?

Micro Swiss CM2 RepRap (V6) 1.75 Nozzle (0.4 mm)

Micro Swiss says the CM2 RepRap nozzle fits "All printers with a E3D V4 / V5 / V6 1.75 Hotend," and names the "Prusa i3 MK2 / MK2S / MK3 / Mini." It doesn't name the MK3S or MK3S+ separately, and we have no MK3S fit record for it, so check fit with Micro Swiss before buying. Separately, Prusa says E3D and E3D-compatible V6 nozzles fit the MK3S and MK3S+, but Prusa doesn't name Micro Swiss. Micro Swiss describes an "M2 Hardened High Speed Steel" tip with a "heat-treated hardness: 68 HRC," a nonstick coating, and a copper chromium zirconium body. It doesn't state a maximum temperature on its page. Prusa's warning about non-brass nozzles with the MMU2S applies here too.

Micro Swiss

Micro Swiss CM2 RepRap (V6) 1.75 Nozzle (0.4 mm, single nozzle (M2902-04))

Best for

Prusa MINI/MINI+ owners who want a hardened-tip nozzle with a copper body.

Skip this if

You only print non-abrasive filaments and want the cheapest genuine spare.

Verified fit

Prusa Research MINI / MINI+ (stock configuration, per the manufacturer)

Specs, strengths, and limitations

Interface

M6x1.0 thread, 7.5 mm thread length, 13 mm overall length, 1.75 mm filament

Hotend design

Copper chromium zirconium body, electroless nickel plated, M2 hardened high speed steel tip (68 HRC), WS2 nonstick coating

Wear-resistant

Yes, per the manufacturer

Maker notes

Micro Swiss product page: fits all printers with an E3D V4/V5/V6 1.75 hotend and names Prusa i3 MK2 / MK2S / MK3 / Mini. It does not name the MK3S/MK3S+, so only the MINI is recorded. Micro Swiss CM2 warranty page: covers wear related to shape (not blockages, jams or coating wear); valid only with filaments with glass, carbon or less abrasive fillers, not Boron Carbide or Tungsten; void above 450°C or if cleaned with cold pulls or needles; ends when CM2 is discontinued. Prusa Knowledge Base also states the MINI is compatible with E3D V6 nozzles. Amazon listing model M2902 matches the Micro Swiss SKU family (M2902-04 for 0.4 mm). Micro Swiss: made in USA, limited lifetime warranty against wear.

Strengths

• Manufacturer names the Prusa Mini as a fit.
• Manufacturer lists an M2 hardened high speed steel tip heat-treated to 68 HRC with a nonstick WS2 coating.
• Manufacturer states a copper alloy body that keeps its strength at higher temperatures than regular copper.

Limitations

• Micro Swiss does not state a maximum temperature on the product page; its CM2 warranty page voids the warranty above 450°C and if cleaned with cold pulls or needles.
• Swap requires tools and a hot nozzle, plus First Layer Calibration afterwards (Prusa).

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if you only print plain PLA, PETG, TPU, ASA and ABS, where the stock brass nozzle does the job. See the replacement nozzles shortlist for other options.

Polymaker PolyLite PLA-CF (Black, 1 kg)

PolyLite PLA-CF is PLA with 8% chopped carbon fiber, for stiff, matte parts. Polymaker's product page says "a hardened nozzle is strongly recommended" and lists "0.4mm+ hardened nozzle required." The TDS (V5.4) and the page's specification block list a 190–230 °C nozzle, a 25–60 °C bed and no enclosure needed. The page's Print Settings block gives 210–230 °C and a 30–70 °C bed. Either set fits the MK3S. The TDS lists a heat deflection temperature of 50 °C at 1.8 MPa, lower than plain PLA.

Polymaker

Polymaker PolyLite PLA-CF (Black, 1.75 mm, 1 kg)

Best for

Stiff, matte-finish PLA parts and prototypes on a printer fitted with a hardened nozzle.

Skip this if

Your printer only has a brass nozzle, or the part will see heat.

Specs, strengths, and limitations

Material

PLA (carbon-fiber filled (8 wt% chopped carbon fiber))

Diameter

1.75 mm

Net filament

1000 g (filament only, not packaged weight)

Format

cardboard spool

Maker's nozzle range

190–230 °C

Nozzle

Abrasive: the maker recommends a wear-resistant nozzle

Strengths

• Manufacturer states 8% chopped carbon fiber gives exceptional rigidity and strength.
• Manufacturer states a matte black finish with virtually invisible layer lines and low shrinkage.
• Manufacturer states it prints with standard PLA settings; the TDS lists no enclosure needed.

Limitations

• Abrasive: Polymaker strongly recommends a hardened nozzle.
• Not suited to heat: the TDS lists a heat deflection temperature of 50 °C (1.8 MPa).
• Cardboard spool: Bambu Lab strongly advises a spool adapter or adapter ring for cardboard spools in the AMS.
• The Amazon listing's bullet points describe plain PolyLite PLA, though its title and model number (PA10001) are the carbon-fiber version. Check that the title says Carbon Fiber PLA before you buy.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-06 against the manufacturer. Price and availability are on Amazon.

Skip it if you still have the brass nozzle fitted, or the part will see heat.

Polymaker Fiberon PETG-rCF08 (Black, 0.5 kg)

Fiberon PETG-rCF08 is PETG with 8% recycled carbon fiber. Its TDS (V1.0) lists a 240–270 °C nozzle, a 60–70 °C build plate and a room-temperature chamber. It says brass nozzle wear "happens frequently," with a brass nozzle lasting "approximately 9h," and highly recommends a wear-resistant nozzle such as hardened steel or ruby. The product page's spec block says "0.4mm+ hardened nozzle required." The product page's spec block says "Enclosure Not needed," but its printing tips say "An enclosed printer is recommended," and suggest Polymaker's preset files on open-frame printers. It recommends drying at 65 °C for 3 hours. The spool holds 0.5 kg. For more filled options, see the carbon fiber filament shortlist.

Polymaker

Polymaker Fiberon PETG-rCF08 (Black, 1.75 mm, 0.5 kg)

Best for

An easy first carbon-fiber PETG for matte functional parts and fixtures on a printer with a hardened nozzle.

Skip this if

You need parts that hold up above about 65 °C, or you want a 1 kg spool.

Specs, strengths, and limitations

Material

PETG (8% recycled carbon-fiber filled)

Diameter

1.75 mm

Net filament

500 g (filament only, not packaged weight)

Format

other

Maker's nozzle range

240–270 °C

Nozzle

Abrasive: the maker recommends a wear-resistant nozzle

Strengths

• Manufacturer states 8% recycled carbon fiber for added stiffness over standard PETG.
• Manufacturer states a matte finish that hides layer lines and PETG-level low warping.
• Prints at ordinary PETG temperatures (240–270 °C nozzle, 60–70 °C bed) per the TDS, with only a short 65 °C / 3 h dry.

Limitations

• Abrasive: Polymaker requires a hardened (or ruby) nozzle of 0.4 mm or larger; brass lasts about 9 h.
• Modest heat resistance: TDS heat deflection temperature is 65.7 °C at 1.8 MPa.
• Only sold in 0.5 kg and 3 kg spools, and Polymaker's enclosure guidance is inconsistent between page sections.

View on Amazon ↗ (opens Amazon in a new tab)Details checked 2026-10-07 against the manufacturer. Price and availability are on Amazon.

Skip it if you still have the brass nozzle fitted, or want a 1 kg spool.

What we left out

• PC. Prusa lists PC for the MK3S+, but neither PC spool in our catalog suits it well. Polymaker PolyLite PC lists "Closure Chamber: Needed (70-100°C)" in its TDS, and Prusa says its enclosure is warmed only by passive heat from the heatbed. Prusament PC Blend Carbon Fiber's material page lists a 285 ± 10 °C nozzle, which runs past the 290 °C figure in Prusa's own comparison table, and it needs a hardened nozzle.
• Softer TPU (below 95A). Prusa says softer filament is harder to print. We kept to the firmer grade.
• Carbon-fiber nylon. Prusa lists nylon and carbon-filled materials for the MK3S+, but several carbon-fiber nylons in our catalog list nozzle ranges up to 300 °C, the very top of the hotend's range.

Checklist before you buy for an MK3S or MK3S+

• Temperatures. Prusa lists a 300 °C nozzle (290 °C in its comparison table) and a 120 °C bed. Check the spool's published ranges against both.
• Material vs. enclosure. PLA, PETG and firm TPU work in the open, though Polymaker's Fiberon PETG-rCF08 page recommends an enclosed printer. ASA and ABS need an enclosure, per Prusa's guides.
• PETG on smooth PEI. Use glue stick, or switch to a powder-coated or satin sheet.
• TPU. Loosen the idler, print at 20–40 mm/s and keep it dry.
• Abrasive fills. Carbon fiber, Kevlar, wood and metal fills need a hardened V6 nozzle, not the stock brass. Keep abrasive spools out of the MMU2S unless you've checked Prusa's MMU documentation.
• Spool weight. Prusament ASA is 800 g, PolyFlex TPU95 is 0.75 kg and Fiberon PETG-rCF08 is 0.5 kg. Everything else here is 1 kg.

Drying, storage and safety

Keep TPU and PETG especially dry. Prusa's drying article says TPU (Flex) is among the filaments "more often in need of drying" than PLA. Each maker's drying setting is on its product card above. Check the spool's own temperature rating before drying it on the spool. Prusament spools changed in October 2025. Prusa says the new black spools resist drying temperatures up to 90 °C. Older Prusament spools have a cardboard core. On the old black spools, the plastic sides are pressed onto that core, and Prusa says they "can be heated up safely up to 45 ºC" unless you add a long screw to hold the sides together. Stock can be on either spool. Our filament dryer vs dry box guide covers the options.

How this page was checked

This is a research-based page. We have not printed these spools on an MK3S or MK3S+ for it, so it contains no test results or scores. The printer limits come from Prusa's MK3S+ 10th Anniversary Edition product page, the MK3S+ support page and handbook (v3.18), the E3D V6 nozzle article, the Original Prusa Enclosure page, the MMU3 compatibility and printer upgrade articles, the Prusa Knowledge Base material guides for PLA, PETG, ABS, ASA and flexible materials, and the drying article. The spool and nozzle statements come from each maker's own pages and data sheets, listed in the sources section. All were retrieved on 2026-10-14. Makers update their pages, so check the current version before relying on a number. Read more in our editorial standards and affiliate disclosure.

PLA: what to check before you buy a spool ↗