Extra thick and comfortable the D-Ring X3 contains the 3 perfect size donut rings. Each kit contains a black, clear and smoke colored ring, intended to be worn around the cock, balls or both. They are made of super strong and stretchy TPE and are phthalate free. The D-ring X3 are soft, stretchy, easy to get on, and help you keep a firm and hard erection. Size: Inner Diameter 0.7” (18mm). Outer Diameter 1.75” (44mm)