I have crated this ring for my girlfriend after i finished my last semi ducted quadrocopter frame. Thats where its design is coming from :D
For men it maybe has to be scaled up a bit. Diameter is ~16mm.
Printed with makerbot replicator.
2mm Rafts, first layer at very slow speed.
Around 10 Minutes.
Leave a make, or a comment if you like it :)