The primary benefit of tungsten carbide bracelets is its scratch resistance. Having a hardness of 9 in Mohs scale it is virtually scratch proof under normal daily wear. Diamond is the only gemstone that has a hardness of 10. Our tungsten carbide bracelets are all made using nickel as binder so they do not contain any cobalt and will not cause any allergic reaction to your skin. Our tungsten bracelets are all made from the highest quality tungsten carbide we do not manufacture rings out of recycled materials. All our tungsten bracelets come with lifetime warranty against craftsmanship defects. This particular tungsten bracelet can be resized easily in a way similar to resizing a watchband all links are hold by pins and they are all detachable. The black color on this bracelet is created with ionic plating which is extremely durable. Fold over clasp for secure closure. It is truly a fashionable and practical piece of jewelry.