Attachment for the Apple Magic Mouse* (the original one, not the Magic Mouse 2).
The magic mouse is the only one I've used on the mac that implements touch scrolling decently, but I found I couldn't use it for more than 10 or 15 minutes without wrist discomfort. If you have the same issue, you may want to give this a try.
The medium version of this attachment makes the mouse usable for me (I've been using various versions of the attachment for about a year). I also included smaller and larger versions that may work better for some.
I print these without support material, with a lot of part cooling, and attached to the build plate with a glue stick. But other settings may work better with other printers.
The layer ridges from the printer will tend to trap dirt. Printing in a darker color, sanding, or using acetone vapor smoothing will help. The part in the picture was printed in PET, sanded, and coated with woodwax