This is an exciting vibrating captive bead ring that is black Anodized titanium over 316L high grade surgical steel. This captive ring comes with two batteries. Vibrating Capsule measures 9mm thick and 18mm long. Size is 14 gauge, diameter 15mm - 5/8" inch (diameter refers to the inside of ring). Entire piece is nickel free. Can be used as vertical hood piercing ring.