MMU3 Enclosed Upgrade for Core One/+

Five filaments, fully automatic switching and a modified top cover that keeps your printer enclosed. The complete kit to turn a Prusa Core One or Core One+ into a five-colour printer.

Load Five Filaments, the Rest Is Automatic

The MMU3 is Prusa's single-nozzle multi-material system, and it talks to your Core One both ways, so the printer always knows what the MMU3 is doing and can recover from loading errors and other edge cases without stopping the job. Thousands of filament swaps happen on their own while you're out of the room. Paint any model in PrusaSlicer or the free EasyPrint app, or download a pre-painted model from Printables, and hit print.

Since the March 2026 firmware update, each filament swap takes around 42 seconds, about 20% faster than before. On a complex five-colour print that can save hours.

Key Specifications

Why the Enclosed Version

The Enclosed and Lite kits use identical MMU3 hardware. The difference is how they mount. The Enclosed kit includes a modified top cover, so your Core One stays fully enclosed with the MMU3 fitted. That matters if you print ASA, ABS, PCCF and other materials that like a warm chamber, and Prusa recommends it for anyone printing advanced materials. A sliding grille lets you print PLA and PETG with the front door closed. Installation takes a little longer than the Lite version because the top cover is swapped.

Core Features

• Up to five filaments in one print with a single nozzle
• Two-way communication with the Core One, with automatic recovery from loading errors
• Clear on-screen instructions on the printer's LCD if it ever needs you
• Around 42 seconds per filament swap with the latest firmware
• Wipe tower, wipe to infill and wipe into object to keep purge waste down
• No vendor lock-in: any filament brand, spools up to 2 kg, no RFID
• Open-source spoolholders, with custom designs on Printables
• Modified top cover keeps the printer enclosed for advanced materials
• Prints single colour as normal, with no impact on speed or quality

Engineered to Waste Less

Every colour change has to purge the old filament from the nozzle. Instead of dropping blobs of plastic next to the printer, the MMU3 purges a small, precise amount into a compact, partially hollow wipe tower. PrusaSlicer can cut waste further by purging into the infill of your part, where it can't be seen, or into a second object on the bed. Prusa puts the result at 73% less wasted filament than competing systems on PLA and PETG at default settings.

Works With the Filament You Already Own

The spoolholders sit beside the printer, so spool size is never a problem and they handle big 2 kg spools. Third-party filament is fully supported, and if you have an unusual spool shape you can download or design your own spoolholder, as the files are open source on Printables.

Compatibility

Designed for the Original Prusa CORE One and Prusa CORE One+, and Prusa lists it for those two printers only. For the 2026 speed improvements, update to printer firmware 6.5.3 and MMU3 firmware 3.0.4 or newer, both free. No hardware changes are needed beyond the standard installation, which includes fitting the supplied 0.4 mm nozzle in place of a high-flow nozzle.

What's in the Box

MMU3 unit (as a kit), buffer cassette, spoolholders for five filaments, modified top cover, PTFE tubing, all mounting hardware and a standard 0.4 mm quick-swap nozzle optimised for MMU printing. Nothing else is needed to start printing in colour. The Core One printer is not included.

Specifications and performance figures are supplied by Prusa Research and may change with firmware updates. Swap times and waste savings depend on the model, materials and slicer settings.