Note: Please measure your finger circumference first and choose the appropriate sizeFashion Black Titanium Cool Men Ring Carbide Jewelry Signet Rings Fit Student Alloy Tungsten Ring for WomenElectroplating process, safe, non-toxic, non-fading, non-allergicNO. 6? Inner perimeter 52?mm, inner diameter 16.5 mmNO. 7 Inner perimeter 54 mm, inner diameter 17.3 mmNO. 8 Inner perimeter 57mm, inner diameter 18.2mmNO. 9 Inner perimeter 59mm, inner diameter 18.9mmNO. 10 Inner perimeter 62mm, inner diameter 19.8mmNO. 11 Inner perimeter 65mm, inner diameter 20.7mmNO. 12Inner perimeter 67mm, inner diameter 22mmNO. 13Inner perimeter 73.6mm, inner diameter 23.5mmMaterial: tungsten steelStyle: exoticModeling: GeometricColour: BlackStyle: men and women