E3D ObXidian vs Brass Prusa Nextruder Nozzle

Who this comparison is for

This page is for owners of a Prusa MK4, MK4S, CORE One, CORE One L, or XL choosing a spare or upgrade nozzle. We compare E3D's Brass Prusa Nextruder Nozzle and E3D's ObXidian Prusa Nextruder Nozzle, both single 0.4 mm nozzles.

E3D also sells High Flow versions of both. We cover those briefly below and in full on the replacement nozzle shortlist. If your nozzle might only be clogged, start with clog diagnosis before you buy anything. If you're not sure your printer uses the Nextruder, our guide to choosing a replacement nozzle explains the different nozzle systems.

How we compared them

This is a research-based comparison. Every detail below comes from E3D's product pages and datasheets for the two nozzles and from Prusa's Knowledge Base and MK4S product page, all listed in the sources. Printer fit comes from our compatibility records, which are built from E3D's pages and checked against Prusa's statement about which printers use the Nextruder. We haven't printed with either nozzle, so nothing here is a measured result of ours. Where E3D describes its own product, such as "ObXidian is really hard," we label it as E3D's claim.

Both nozzles come from the same maker and share one design, so this is a closer comparison than most. E3D publishes the same kinds of figures for both: maximum temperature, mass, identification dots, and a flow-rate table. It doesn't publish a hardness figure or a wear test for either. There's no independent wear or flow test on this page.

Side-by-side specs

The flow figures are E3D's, measured at 220 °C for PLA, 240 °C for PETG, and 260 °C for ASA.

Wear resistance and materials

This is the whole difference between the two.

• ObXidian. E3D says "ObXidian is really hard, making it the perfect nozzle for printing abrasive/filled polymers with," and that this "is achieved by pairing a tool steel insert with our E3DLC™ coating." Its product page opens that claim with "a wear resistance that is orders of magnitude higher than any other E3D nozzle." E3D publishes no hardness figure. Those are E3D's claims.
• Brass. E3D's datasheet marks every brass size "No" under "Abrasion resistant?" Prusa says "The Prusa FFF printers are equipped with a brass nozzle," that "Brass has excellent heat conductivity and is tough enough to print most common filaments," and that "when using abrasive filaments, the brass nozzle tends to wear too quickly."

E3D is open about the ObXidian's limits. It says "some new materials which include aggressive fillers, including but not limited to Polymaker's Fiberon range (PA612-CF, PA6-CF, PA6-GF and PA12-CF), can cause significant wear on even ObXidian nozzles," and that the nozzle is "not everlasting under extreme material conditions." Its FAQ adds that glow-in-the-dark filaments contain strontium aluminate, which, printed "at very high movement speeds," can remove the E3DLC coating. E3D also says it has "successfully run multiple kilograms of glow in the dark filament through an ObXidian Nozzle," and advises: "If in doubt, print slow."

Our guide to nozzles for abrasive filaments covers which filaments count as abrasive and when a wear-resistant nozzle is worth it.

Flow and temperature

The two are close on both. E3D's datasheets list these maximum volumetric flow rates for the 0.4 mm nozzles:

E3D lists a 300°C maximum temperature for both. The printer sets the real limit, though. Prusa's MK4S page lists a maximum nozzle temperature of 290 °C for the MK4S, and its comparison table gives the same 290 °C hotend limit for the CORE One and XL. So on those printers, neither nozzle's 300°C rating is usable. Don't print above what Prusa allows for your printer.

Sizes and the high-flow versions

E3D sells the brass nozzle in 0.25, 0.4, 0.6, and 0.8 mm, and the ObXidian in 0.4 and 0.6 mm only. Both listings compared here are 0.4 mm. E3D warns that "Some filled materials contain particles that are close to, if not larger than, some of the smaller industry standard nozzle sizes, including up to 0.4mm," so check your filament maker's minimum nozzle size before you print a filled material through a 0.4 mm ObXidian. Our nozzle sizes guide explains the trade-offs.

E3D also sells High Flow versions of both nozzles, in 0.4, 0.6, and 0.8 mm. E3D says they keep "the exact same form factor" as its standard Prusa nozzles and use "a unique custom internal geometry to increase the surface area for improved thermal transfer to the filament." Its datasheets list 20 mm³/s for PLA at 220 °C for both 0.4 mm High Flow nozzles, against 15 and 16 mm³/s for the standard ones above. E3D also notes that "there are no official profiles built into Prusa Slicer" for them, so you'd edit the volumetric flow limits yourself. Both High Flow nozzles are on our replacement nozzle shortlist, with the same printer fit as the two compared here.

Printer fit

In our compatibility records, both nozzles fit the MK4, MK4S, CORE One, CORE One L, and XL.

• E3D lists the same seven printers under "Printer Compatibility" on both product pages: "Prusa MK3.9," "Prusa MK3.9S," "Prusa MK4," "Prusa MK4S," "Prusa XL," "Prusa CORE One," and "Prusa CORE One L."
• Prusa says "Every MK4S, MK3.9S, MK4, MK3.9, XL, CORE One/+, CORE One L/+ and Signature Oak printer is equipped with a Nextruder Hotend."

E3D's pages don't separate the CORE One "+" revisions, so we rely on Prusa's statement that they share the Nextruder. The MK3.9 and MK3.9S are named by E3D, but they aren't in our printer records, so we make no fit claim for them. E3D's older datasheets for both nozzles still say "Compatible with: Prusa Mk4 & Prusa XL," and the Amazon listings for both, in our catalog records, name only the MK4 and XL. E3D's current product pages name more printers, and our fit follows those. Prusa's Nextruder list doesn't include the MINI / MINI+ or the i3 MK3S / MK3S+, and E3D doesn't name them for these nozzles, so we make no fit claim for them. The shortlist covers nozzles for those printers.

Fitting and cleaning

Both nozzles have what E3D calls "an all-metal filament guide which means that Nextruder's filament path is entirely metal," and E3D's brass page says "Changing a nozzle on your Prusa printer just got much easier!" Prusa publishes a separate nozzle-change guide for each Nextruder printer, and says its methods are "fully compatible with both Prusa Nozzle and Prusa Nozzle CHT diameters." E3D's ObXidian page also lists a "How to change your Genuine E3D Prusa Nozzle" guide under Documentation. Follow the guide for your exact model.

Two setup points:

• Slicer settings. E3D's FAQ for the brass nozzle answers "No" to whether you need new firmware or a PrusaSlicer profile change. Prusa says to select your printer model and the nozzle diameter you're using in PrusaSlicer's Configuration Wizard, and to set a different nozzle size on the printer under Settings, then Hardware. Prusa's MK4S page lists a "High-flow Prusa Nozzle brass CHT - 0.4 mm" as the nozzle provided on the MK4S and CORE One, so check that your profile matches the standard-flow nozzle you've fitted.
• Cleaning a coated nozzle. Prusa says "An acupuncture needle or a brass brush can damage the coating," and "For ObXidian nozzles, we do not recommend cold pulls, as they can tear off the WS2 coating." It recommends a non-abrasive cloth outside and cleaning filament inside. Prusa calls the coating WS2, while E3D calls its coating E3DLC. We found no cleaning guidance on E3D's ObXidian Nextruder pages.

What E3D says each is for

• ObXidian. "The perfect nozzle for printing abrasive/filled polymers," with "considerably less plastic build-up around the Nozzle." That's E3D's claim.
• Brass. E3D describes it as a "high-quality" Nextruder nozzle with an all-metal filament guide, without a wear claim. Prusa's description of brass in general is that it suits "most common filaments."

E3D

E3D ObXidian Prusa Nextruder Nozzle (0.4 mm, single nozzle (PRUSA-MK4-NOZZLE-OBX-AS-0400))

Best for

Nextruder owners (MK4, MK4S, XL, CORE One, CORE One L) who print carbon-fiber, glass-fiber or glow filaments regularly.

Skip this if

You print only plain PLA and PETG, where a brass Nextruder nozzle does the job.

Verified fit

Prusa Research MK4S; Prusa Research CORE One; Prusa Research CORE One L; Prusa Research XL; Prusa Research MK4 (stock configuration, per the manufacturer)

Specs, strengths, and limitations

Interface

Prusa Nextruder nozzle with all-metal filament guide

Hotend design

Tool steel insert with E3DLC coating

Part rated to

300 °C (your printer's own hotend limit may be lower)

Wear-resistant

Yes, per the manufacturer

Maker notes

E3D product page: compatible with Prusa MK3.9, MK3.9S, MK4, MK4S, XL, CORE One & CORE One L. MK3.9/MK3.9S are not in printers.json. Amazon listing says MK4 and XL only; E3D's current page (manufacturer) also names MK4S, CORE One and CORE One L. Prusa Knowledge Base: every MK4S, MK3.9S, MK4, MK3.9, XL, CORE One/+, CORE One L/+ and Signature Oak printer has a Nextruder hotend. Each nozzle has its size engraved (E3D).

Strengths

• Manufacturer states wear resistance orders of magnitude higher than any other E3D nozzle, for abrasive/filled polymers.
• Manufacturer states the E3DLC coating adds non-stick properties for less plastic build-up.
• Manufacturer names the MK4, MK4S, XL, CORE One and CORE One L as compatible.

Limitations

• E3D lists a 300 °C maximum recommended printing temperature.
• E3D warns aggressive fillers (e.g. Polymaker Fiberon PA612-CF, PA6-CF, PA6-GF, PA12-CF) can still cause significant wear, and some filled materials can jam nozzles of 0.4 mm and smaller.

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

E3D

E3D Brass Prusa Nextruder Nozzle (0.4 mm brass, single nozzle (PRUSA-MK4-NOZZLE-AS-0400))

Best for

Nextruder owners who want a like-for-like spare for everyday PLA, PETG and ASA.

Skip this if

You print carbon-fiber, glass-fiber or glow filaments.

Verified fit

Prusa Research MK4S; Prusa Research CORE One; Prusa Research CORE One L; Prusa Research XL; Prusa Research MK4 (stock configuration, per the manufacturer)

Specs, strengths, and limitations

Interface

Prusa Nextruder nozzle with all-metal filament guide, 1.75 mm filament

Part rated to

300 °C (your printer's own hotend limit may be lower)

Wear-resistant

No

Maker notes

E3D product page: compatible with Prusa MK3.9, MK3.9S, MK4, MK4S, XL, CORE One & CORE One L (its spec line reads 'MK4, MK4X, XL, CORE One & CORE One L', apparently a typo for MK4S). MK3.9/MK3.9S are not in printers.json. Amazon listing says MK4 and XL only; E3D's current page names the MK4S, CORE One and CORE One L as well. Prusa Knowledge Base: every MK4S, MK3.9S, MK4, MK3.9, XL, CORE One/+, CORE One L/+ and Signature Oak printer has a Nextruder hotend.

Strengths

• Manufacturer names the MK4S, XL, CORE One and CORE One L as compatible.
• Manufacturer states an all-metal filament guide makes the Nextruder filament path entirely metal and speeds up nozzle changes.
• Manufacturer lists 1.75 mm input and a 300 °C maximum temperature; size is engraved on each nozzle.

Limitations

• Brass is not wear resistant: E3D sells ObXidian versions for abrasive/filled filaments.
• Standard flow; E3D sells a separate High Flow version for faster printing.

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

Verdict: which should you buy?

Choose the E3D ObXidian if…

• You print carbon-fiber, glass-fiber, or glow filaments, which wear brass quickly.
• You want E3D's non-stick coating, and you'll follow Prusa's cleaning advice for coated nozzles.
• You're happy that E3D publishes no hardness figure, and you'll avoid the extreme fillers E3D warns about.

Choose the E3D Brass if…

• You print PLA, PETG, ASA, and other unfilled filaments.
• You want a 0.25 or 0.8 mm nozzle later, sizes E3D doesn't sell in ObXidian for the Nextruder.
• You want a nozzle you can clean with the usual methods, without a coating to look after.

Safety and limits

How this page was checked

Every material, figure, size, and fit detail above comes from the E3D and Prusa pages in the sources section, retrieved on 2026-10-11, and printer fit comes from our compatibility records. We haven't printed with either nozzle for this page, so nothing here is a measured result of ours. E3D's product pages name seven printers, while its older datasheets name only the MK4 and XL. We follow the current product pages, backed by Prusa's statement about which printers use the Nextruder. The flow, mass, and identification figures are from E3D's datasheets, not our own measurements. We searched E3D's product pages and datasheets for both nozzles and found no hardness figure or wear test. The 290 °C limits come from Prusa's MK4S product page and its comparison table. The MK4-and-XL wording on Amazon comes from our catalog records of those listings, not from E3D. Read more in our editorial standards and affiliate disclosure.

Nozzles: what to check before you buy ↗