Waterproof💧💧💧, Stainless Steel - Waterproof. and Cubic Zirconia Crystals,18K Gold, Hypoallergenic, Nickel Free SIZE: 18mm Diameter Designer Note: Classic with a twist. These 18mm diamond hoops are the ultimate in versatile sparkle. Dress them up or down, they’re perfect for any occasion and made from waterproof 18K gold over Stainless Steel - Waterproof. featuring stones that shine like real diamonds.