Doc Johnson Novelties Optimale Men's Sexual Health and Wellness line. This powerful Vibrating C-ring is made for pleasuring you and your partner: featuring a textured yet soft stretchable silicone ring for easy use and a removable bullet in a nubby sleeve for comfortable stimulation. The push button offer 10 unique functions. Wear the ring atop the shaft for targeted clitoral stimulation or under the shaft for targeted clitoral stimulation or under the shaft or testicles for self-stimulation. Batteries included. Dimensions Inner Diameter: 1.5 inches, inner Circumference: 4.71 inches. Total length 2.70 inches. Usable Length 2 inches. Width/Diameter 2 inches. Circumference 6.30 inches. Video. 18.