You never know when you might find yourself in need of a selection of cock rings. These black rubber Os are the perfect penis enhancement tool. Simply select one or more of the rings in this 3-piece set and arrange them on your cock for superior support. Use one alone or experiment with all three at once to provide extra enhancement for you and three times the sensation for your partner. Small diameter is 1.75in. Medium diameter is 2in. Large diameter is 2.5in.