Ruthenium-colored sterling silver . Engraved logo details. MEN'S SIZING:,XXS: Size 5 - inside diameter 17.8mm / circumference 56.0mm,XS: Size 6 - inside diameter 18.5mm / circumference 58.0mm,S: Size 7 - inside diameter 19.1mm / circumference 60.0mm,M: Size 8 - inside diameter 19.7mm / circumference 62.0mm,L: Size 9 - inside diameter 20.4mm / circumference 64.0mm,XL: Size 10 - inside diameter 21.0mm / circumference 66.0mm,XXL: Size 11 - inside diameter21.7mm / circumference 68.0mm