IVY Classic's Cobalt Advantedge (Registered Trademark) Bi-Metal Hole Saw Kits 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" 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. IVY Classic Industries is dedicated to producing a comprehensive, quality line of power tool accessories and hand tools.