Distinctive gold bits, bearings and pivot pin signify the longest lasting, fastest cutting, easiest adjusting solution for cutting holes in sheet metal. Malco® hole cutters quickly install into the chuck of any corded or cordless drill as small as 6.35 mm. Lightweight aluminum frames make these accessories extremely portable for a variety of hole cutting applications in sheet metal including 20 ga 1.02 mm galvanized steel. A compact model HC1 hole cutter is adjustable for making 51 to 305 mm diameter holes. A combination English/metric diameter gauge is included on the adjustable pivot slide for both models and both models use the same mill type cutter bit and replacement parts. Malco® Hole Cutter, Adjustable Standard, 2 to 12 in Maximum Cutting Dia, 1-1/8 in Cutting Depth, HSS Tool, Uncoated, Black/Gold, Applicable Materials: HVAC, Aluminum, 20 ga Mild Steel and 20 ga Galvanized Steel