The smart ring is made of high quality stainless steel, which is durable and rust resistant. It has the functions of automatic dialing, automatic SMS, automatic e-mail, user-defined open web page, and custom profile. The smart NFC ring is attractive and creative, the stylish appearance is also suitable for pairing with any kinds of looks. Item Name: NFC Smart Ring Material: Stainless Steel Features: Anti-rust, NFC Function, Dragon Pattern Size Details: US 6: Diameter: 16.4mm/0.65" (Approx.) US 7: Diameter: 17.3mm/0.68" (Approx.) US 8: Diameter: 18.1mm/0.71" (Approx.) US 9: Diameter: 18.9mm/0.74" (Approx.) US 10: Diameter: 19.7mm/0.78" (Approx.) Notes: Due to the light and screen setting difference, the items color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x NFC Smart Ring