This closed coat silcon carbide belt uses a heavy "X" ( grits 100 or finer) or "Y" (grits 80 or coarser) weight resin bond polyester backing. Its silcon carbide grain will out last aluminum oxide on softwoods. This belt cuts freer and will not load as readily. It is also used for grinding glass, ceramic, solid surface materials, stone, concrete block, nonferrous metals, titanium and stainless steel. Silicon Carbide is next to diamond in hardness, Silicon Carbide, characterized by its sharp sliver like grains makes it superior for its ability to penetrate with light cutting pressures. It is primarily used for grinding nonferrous materials such as brass, copper, bronze and aluminum. Other applications of Silicon Carbide include grinding of glass, wood, rubber and plastics. It is used also to finish polyurethanes, primers, lacquers and sealers. Silicon Carbide is the grain of choice for certain finishes on stainless steels. Silicon Carbide products are typically black in color. Resin Bond Backings - Resin bond backings offer greater resistance to heat , are more durable in heavy stock removal applications and provide the best all-around bond system.