The GoFit® Interchangeable Ring Roller RFX is a revolutionary massage roller and a part of our Interchangeable Massage System. This roller gives you the ability to rearrange the included rings and control your contact points where you need them. It uses specially designed, interchangeable massage rings to target virtually every muscle group in the body. The Ring Roller comes with 10 interchangeable rings in 5 different sizes for adaptive massage. They are made of molded foam with rounded studs, ideal for reflexology massage. Simply unscrew 1 wheel to rearrange the rings and transform the roller to target plantar fasciitis, carpal tunnel, and other sore muscles. Overall length is 7.25 in. and wheel diameter is 3.125 in.