Zheng-like pocket gears

I loved the idea of Zheng3's pocket gears http://www.thingiverse.com/thing:185155 but discovered that the magnets I bought were 6 mm rather than truly .25" and were too loose. This is my attempt to make something similar for 6 mm magnets, without the grace and fine lines of his design but with two mechanical improvements:

• a stepped center hole that lets the magnet rest against a shoulder, hopefully keeping it more secure
• a backing plate that keeps the gears in place on your shirt so they turn more easily

Edit: From a suggestion in the comments, the backing plate holes now have the same number of sides as the gears so the magnets should fit the same, and the parts are customizable to tweak the magnet diameter.