Changing materials and print cores on the Ultimaker 3 – Ultimaker Support
2018 Ultimaker 3 UM3 PP ThreadTube PrintCore heater break Extruder throat, Non standard parts for 3mm filament 3D printer|3D Printer Parts & Accessories| - AliExpress
1Set UM3 Extra Print Cores AA/BB UM Print Core AA 0.4mm BB 0.4mm for Ultimaker3 / Ultimaker 3 Extended 3D Printer|3D Printer Parts & Accessories| - AliExpress
Ultimaker Print Core AA 0.4mm nozzle - Local Makers Projects