IVY Classic 28117 8 Piece Cobalt Advantedge Bi-Metal Locksmiths Hole Saw Kit are designed for their outstanding cutting performance and convenience. Constructed out of bi-metal with an M-3 cutting edge, these hole saws cut a variety of materials such as stainless and mild steel, non ferrous metal, plastic and wood with a 1-1/2-inch cutting depth. Additionally, their variable pitch, positive rake tooth design minimizes tooth wear and a thick backing plate prevents thread stripping and increases torque. These kits come in sturdy plastic cases and contain the most popular sizes for the professional. Contains hole saws: 7/8", 1", 1-1/4", 1-1/2", 1-3/4" & 2-1/8". Contains arbors: 2H & 4H.