Simple in form. yet intended to be worn with purpose. These steel cock rings are as elegant as they are strict. There is no give here! Simply slip a Trine over the penis like a halo. encircling the scrotum for a supremely snug fit. Revel in the pleasure! The Trine Steel Rings can also be used to fit most harness systems.Measurements: Ring inner diameters: Small: 3.9 cm (1.53 inches). Medium: 4.6 cm (1.82 inches). Large: 5.2 cm (2.05 inches). All rings are 7 mm thickMaterial: Steel