This ring is Tungsten Carbide TC850 with a black carbon fiber inlay in a satin finish with high polished edges. The band is 8 mm wide. Tungsten Carbide TC850 is nearly 85% tungsten carbide, forged in a sintering process by firing tungsten with carbon powder at 6,200 degrees Fahrenheit producing this lustrous color. Tungsten Carbide TC850 is ten times harder than 18k gold, is scratch resistant, tarnish resistant, and will remain polished forever. So tough and rugged, it epitomizes todays man more than any other and is perfect for a mans active lifestyle. This ring is Comfort Fit and comes with a Lifetime Warranty. It is available in smaller and larger sizes. Price shown is for up to size 13. Lifetime sizing is available on all tungsten rings. USPS Priority shipping is free to all US addresses. Security Jewelers is an 85 year old family store located in Duluth, MN. We are members of the American Gem Society. All diamonds used in our jewelry are conflict free and 100% compliant with the Kimberly Code of Conduct. We are also major dealers in diamonds mined in Canada. All our gold items are responsibly sourced and the majority are made from environmentally processed recycled gold. We are also members of nodirtygold.org.