It is difficult to clean the Apple Mighty Mouse's mouse-ball without breaking off the bottom ring, which is both tabbed and glued on to the mouse.

This replacement friction fits in place. Start in the front and secure it around the sides to the back. It may require a little bit of sanding or shaving. There are 'gripping' holes near the rear, but I had to sand them a little. I'm not convinced they're doing any gripping.

Bonus: customize your Apple mouse with colors!

This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/4fq2bL2t0fH

Printed at 0.3mm layer height, 120mm/sec, on Replicator 1. Worked pretty well without much finishing.

Watch your layer height. 0.4mm left the front end weak at the wire cut-out. That area will need some tenderness when sanding.