The abrasive surface is permanently fused to a stainless steel pad. The surface texture is comparable to a 100 grit abrasive. They are ideal for holding smooth or slippery applications with a minimum of clamping pressure. Individual diamond particles transfer holding pressure to a very small and well distributed area, providing superior holding with minimal surface marking. The diamond surface also provides unparalleled wear resistance. The pad is made from 17-4 stainless steel which provides high strength as well as protection against chemical and environmental corrosion. Heat treated to Rc 43/46. Counter bored hole for front mounting with a socket head cap screw.