Customized version of http://www.thingiverse.com/thing:44815
Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing\_id=44815
Using the following options:
type = 1
groove = 2
margin = 0.1
weight = 11
diameter = 11
edges = 1
cursor = 100
$fn = 50
The author marked this model as their own original creation. Imported from Thingiverse.