Grinding wheel specifications and models follow unified industrial standards, which mainly include shape code, overall dimensions, abrasive grain, grain size, hardness, binder and maximum safe linear speed. Common types are flat wheel (P), cup wheel (WA), dish wheel (BW) and depressed center wheel (T). Dimensions are marked as outer diameter × thickness × bore in millimeters. Main abrasives consist of brown fused alumina (A) for carbon steel and cast iron, white fused alumina (WA) for hardened steel and alloy steel, and green silicon carbide (GC) for hard brittle materials like cemented carbide and stone. A larger grain size number means finer grains: coarse grains are for rough grinding and rust removal, while fine grains are for precision grinding and polishing. Ceramic bond (V) features high stability and heat resistance, and resin bond (B) boasts good flexibility and strength. Always operate within the rated maximum linear speed to prevent safety accidents. A typical marking example is P 200×25×32 A 60# M V 35m/s.