Top selling Wedding Band Ring 8mm for men or women. This beautiful black tungsten carbide ring is 8MM in width with silver color stationary mechanical gear design over black carbon fiber inlay. If you are looking for a ring that is scratch proof and forever keep its shine, then our Tungsten Carbide rings are for you. Tungsten Carbide is ranked second hardest next to diamond on the Mohs scale, diamond being a 10 followed by Tungsten Carbide as 9. Mens Wedding Rings Black. Hypoallergenic. Our rings will not cause skin irritations or turn your fingers green. Due to the Hardness of Tungsten, these rings can be laser engraved, but not hand engraved. They CANNOT be stretched. Men's Tungsten Wedding Bands / Gear Wheels Wedding Bands Black and Silver.