This is a colorful titanium anodized over 316L surgical steel nose hoop ring available in your choice of purple, blue or green. The flat head size is 2.5mm. This nose piercing body jewelry is designed to universally fit anyone. The size is available in 18 or 20 gauge and 8mm-5/16 or 10mm-3/8 of an inch. The entire piece is nickel free.