The new Ultimaker 3 comes with a spool holder for 2 750 gram spools. I would like to print with larger spools. Therfore I have designed this upgrade. The lower spool holder easily clicks in the UM 3. For the upper spool holder only 2 m4 nuts and bolts are needed to connect the upper spool holder to the upper base. I printed it in black for a clean look. The hook can be mounted with the orignial screw near the extruder. I have not been able to do a lot of testing with the spool holder and the guiding of the filament. If you have any idea to improve, feel free to modify the model yourself or ask me.