This 4-pack of o-rings lets you fit a variety of dildo sizes into your strap-on harness, or find the right size (or combo) for use as cock rings.
Measurements: 1.25" (3.2 cm), 1.5" (3.8 cm), 1.75" (4.5 cm), and 2" (5 cm) in diameter. Nitrile 70 (NBR), rubber (latex-free)