Black Carbon Fiber Inlay & CZ Tungsten Carbide Unisex Ring Wedding Band Sizes 6-15.5- 8mm Black Carbon Fiber Inlay & CZ Tungsten Carbide Unisex Ring Wedding Band Sizes 6-15.5- 8mm Comfort fit- the inside edges are perfectly shaped for maximum comfort. Tungsten Rings are the most wear-resistant rings available on the planet. Each Tungsten ring is individually hand-crafted using assorted diamond abrasives and polycrystalline diamond tooling. Ideal for Wedding- Engagement -Anniversary -Birthday- Christmas - Gift