TKO Hole Cutters offer the most efficient and clean cutter replacement for traditional knockouts, by making smooth holes in a fraction of the time at a fraction of the cost. Specifically designed to cut sheet metal, TKO cutters will even cut stainless steel with fine grained, carbide tips. The innovative design includes the exclusive SmoothStart replaceable pilot drill, which guides the cutter to the surface, avoiding cutter damage and providing smoother holes. Hole size 1-1/8 in. Integrated arbor provides solid rotation SmoothStart pilot drill prevents bit from "walking" on smooth surfaces Precision ground carbide teeth for fast cutting of clean, burr-free holes Designed specifically for sheet metal and stainless-steel Built-in over drill flange prevents penetration beyond the sheet metal Carbide tips cut up to 1/8 in. thick steel Ejection spring effortlessly ejects slug Do not "Rock" cutting edge