Silicone c-rings are broad for comfort and safety. The Super Soft Ring is stretchier, so it is easier to put on. Great for beginners, too. You don't have to put it on before an erection occurs. Made from a unique formula of Ultra-Premium Silicone: Easy To Clean, Eco-Friendly, Hypoallergenic, Hygienic, Boilable, Bleachable and Dishwasher Safe. Diameter is 1.5 in.