Trizact discs are made of a special grain that gives high stock removal while creating a very even finish without deep scratches. Particularly good for removing TIG welds in stainless-steels leaving a predictable flat surface for final finishing, used in conjunction with the 42-496 backing pads. This particular one has a 75mm removal centre that can be used in conjuction with a 42-498 backing pad once the outer area has worn away