United StatesOriginal Prusa MMU3 assembled unit (for MK4S/MK3.9S)
The Original Prusa Multi Material Upgrade 3 (MMU3) is our latest solution for printing with up to five filaments at the same time using a single nozzle and with high speed and low waste. As a smart add-on for the Original Prusa 3D printer, it enables automatic switching between loaded materials. MMU3 is fully supported in PrusaSlicer by an easy Multimaterial painting tool, and it offers efficient and filament-saving color printing to everybody.
What is MMU3?
It’s exactly what it sounds like—an optional add-on that enhances your single-extruder printer so it can print with up to five colors simultaneously. The Prusa MMU3 is the fastest single-nozzle multi-material solution available, delivering excellent quality with minimal waste.
The MMU3 contains five filament insertion points. Load up to five colors of your choice, slice the object in PrusaSlicer, and start the print. The system automatically selects filament using the selector, loads it into the extruder and the printer starts printing. Based on your project settings, the MMU3 unit will automatically select the right material, and feed it into the nozzle. When a material change is needed, the MMU3 unloads the current filament, purges the nozzle with minimal waste, loads the new filament, and continues printing. You can also use the MMU3 to set up color changes at specific layers, with the unit handling color switching automatically. All you need to do is remove the finished model from the print sheet.
Designed for seamless operation and intuitive troubleshooting, the MMU3 offers the best userexperience—the only more advanced solution in this category is the Original Prusa XL, which features up to five independent print heads.
Main Features
FASTEST SINGLE-NOZZLE MMU PRINTING
Thanks to its fine-tuned firmware and smart design, the MMU3 delivers extra-fast filament changes, averaging between 35 and 45 seconds. A single multi-material print can involve thousands of filament changes, so every second saved adds up—cutting total print time by hours.
EFFICIENT MULTI-COLOR PRINTING
Every time you switch filaments, you need to purge the previous material from the nozzle to prevent color contamination. The MMU3 features a smart nozzle cleaning method similar to the cold pull technique, which softens the filament just enough to pull it out, removing any residual material, debris, or contaminants. This enables clean color transitions with only a minimal amount of filament extruded into the efficient wipe tower—a compact, partially hollow block next to the printed object where the filament is purged and the pressure in the nozzle is stabilized. All purged filament goes into one location, so you don’t have to worry about bits of plastic piling up around your printer.
We offer multiple ways to save filament and further reduce plastic waste. PrusaSlicer provides options like wipe-to-infill, where the printed object’s infill is used instead of a wipe tower, or wipe-to-object, where another object serves as the wipe tower. The latter will result in a very colorful print, but if you need a functional part or plan to paint it later, it’s an excellent way to minimize plastic waste.
CHT VS STANDARD NOZZLE
The high-flow nozzle in the MK4S allows for much faster printing. However, when using the MMU3, the standard nozzle makes much more sense. Why? While the MMU3 works fine with a high-flow nozzle, the increased volumetric flow results in higher filament waste during printing. In other words, the MMU3 delivers the best performance, the same speed, and the highest efficiency (lowest waste) when combined with the standard nozzle in both MK4 and MK4S.
So, if you order a standalone MMU3 for the MK4S you will receive it along with the standard nozzle. In the MK4S/MMU3 bundle, you will receive both nozzles in the package - the standard one as well as the high-flow nozzle. For assembled MK4S in a bundle with MMU3, the standard nozzle will be pre-installed on the printer by default.
SMOOTH FILAMENT FEEDING SYSTEM
We’ve designed the filament feeding system for smooth and reliable operation. The filament travels through a PTFE tube into a buffer cassette and from there, it continues via another PTFE tube to the MMU3. This setup ensures smooth filament movement with minimal resistance while preventing tangling.
SMART FIRMWARE WITH TWO-WAY COMMUNICATION
The MMU3 firmware features seamless two-way communication between the unit and your Prusa 3D printer, ensuring smooth, reliable, and autonomous operation. If an issue occurs, the unit can diagnose and resolve it automatically while providing real-time status updates and detailed error descriptions directly on the printer’s LCD screen. You can control the MMU3 via the printer’s LCD menu or the unit’s onboard buttons for quick manual adjustments—making multi-material printing even more intuitive and hassle-free.
RELIABLE PERFORMANCE AND EASY MAINTENANCE
Thanks to smart two-way communication between the unit and the printer, dependable filament switching, and a robust design, the MMU3 can handle thousands of filament changes without any manual intervention. Combined with its easy maintenance, this ensures a smooth and hassle-free user experience.
PRUSASLICER MAKES MMU PRINTING EASY
PrusaSlicer offers full support for the MMU3, providing an intuitive way to apply colors to different parts of your 3D model. With tools like the customizable brush, smart fill, and bucket tool, you can easily paint your model and assign each color to a specific extruder. PrusaSlicer optimizes material usage with features like the smart wipe tower, wipe-to-infill, and wipe-to-object, reducing filament waste and ensuring sharp color transitions.
MMU3 package includes
- Original Prusa MMU3 assembled unit (for MK4S/MK3.9S)
- Prusa Nozzle brass 0.4mm
- The Frog Prince (multi and single colour fairytale model) by Loubie3D
- Articulated Sea Turtle (singlecolor and multicolor) by Jopek Design
- Chibi Wolverine by FunserviceStl
- Mini Viking by Wekster
- Astronaut sitting on moon by RustyFuzzdoor
- Kingfisher [MMU] Three versions by Sidnaique
- Model 7: Buggy by 3D Sets
- Lizard (multi-material remix) by Cipis
The Original Prusa MMU3 is our latest solution for printing with up to five filaments at the same time with high speed and low waste. As an add-on for the Original Prusa i3 MK3S+ and MK4, it enables automatic switching between loaded materials. MMU3 is fully supported in PrusaSlicer by an easy multi-material painting tool, and it offers efficient and filament-saving color printing to everybody.