This is a rotating base for the Scroll Wheel. It has a bearing captured inside that allows the Scroll Wheel to pivot freely around its axis. This is for printers with a long Z axis to help minimize the bend in the PTFE tubing. In addition to the printer parts, you'll need a standard inline skate bearing:
one 8 x 22 x 7 (608ZZ) bearing
Assembly The three printed parts are the axle, the shell and the base.
Insert the axle into the bearing and then press the bearing into the recess in the back of the shell. Just push it in enough so the bearing is flush. Then insert the axle into the base. I used a dab of CA glue to keep it in place. Verify that it spins freely - a dry run without adhesive is advised.
Finally, apply a piece of the hook material supplied with the Palette to the top of the shell. Attach your Scroll Wheel. You can use two M3 cap screws to mount the base to your printer.
I attach this to an 10mm x 10mm auxiliary tower on my large UltiBots D300VS delta printer. The brackets to mount the tower are here: https://www.thingiverse.com/thing:2457618