Swingee is really easy design to put on your keys. Your not gonna feel bored anymore. Just swing and swing. You can do multiple colors. Like me :D

There is 16, 19, 22 version. That number means ⌀.

How to measure your finger:

You can measure your finger with tape measure like this:

Then transform CM(6.2) to MM(62).

Divide milimetres by Pi(3,14). (19.74)