Silicone Tribal Rings Black is high quality multiple-use rings enhance, support, and stimulate. Sturdy, soft, stretchy and pliable. Silicone. Diameter: 1.15 inches small cock ring. Diameter: 1.3 inches wide large cock ring. Phthalate free, non-toxic materials: silicone. Silicone Tribal Rings is a registered trademark for California Exotic Novelties. New image added January 7, 2012.