The NOS by Fun Factory.

The Nos has 4 powerful speeds and one rhythm pattern. The non circular design helps it stay in place on the penis. This ring is very versatile, it can be worn with the two motors up if a clitoris is involved or worn down for self pleasure for folks with a penis. It can also be placed on a favourite dildo or vibrator for added stimulation. The Nos is rechargeable, waterproof and made of super soft stretchy silicone. Fun Factory has knocked this one out of the park with the small but super powerful NOS penis ring.