Saitech Attacker, made with 3M cubitron, is the United Abrasives grinding wheel, providing extremely fast stock removal on hard metals with minimal pressure.  Applications:  Stainless Steel, High Tensile Alloys, Ferrous Metals such as Iron, Steel and Welds.  4" diameter, 1/4" thick, Type 27 (depressed center), 5/8 bore, no hub.  For right angle grinders.