The Type 1A1W grinding wheel with diamond abrasive (D grit designation) and electroplated bond is designed for grinding holes in cemented carbides, glass, ceramics, silicon, graphite, and more.
On the other hand, a borazon abrasive (B grit designation) grinding wheel is intended for grinding holes in tool steels, hardened, high-speed, bearing, stainless, and other types of steel.