PAIR of Synthetic Opal Ball Ion Plated Captive Bead Rings - 16g Body Jewelry PAIR of Synthetic Opal Ball Ion Plated Captive Bead Rings Fast shipping - Select your color from the above menu Material: Ion Plated 316L Surgical Steel - Gem is Synthetic Opal Internal Diameter: 5/16" (8mm) - Opal Balls are 3mm Ordering a quantity of one gets you a pair!