Spinner Button Twist with Holes

I really loved the design behind the twist together spinner button caps from a [design by 2ROBOTGUY](http://www.thingiverse.com/thing:1802260). But, I hated that they covered the whole bearing. I have bearings with different color seals and looks, and wanted to be able to see them.

I just added a ring of holes to give visual access to the bearing underneath. An added bonus is that holes give the cap a little non-slip effect.