After changing PLA filament brands, it was snapping unexpectedly on the guide. By adding in this wheel, it prevents acute curvature of the filament. The wheel is quite floppy, so if the spool shifts around on the holder, it'll compensate. Just be aware that support material will create an inner wall inside the first bearing wheel. Remember to cut all of it out. Print each part twice. Clean the holes out with a sharp tool and press together firmly to test each connection. Add the outer wheel halves over the inner ones and test for smooth spin. Installation. 1. Clamp each inner wheel half over the Ultimaker 2 filament guide. 2. Clamp each outer wheel half over that. 3. Give it a spin. 4. Position filament. SLDPRT is included in case anyone wants to make it better.