HSS Bi metal hole saw kit comes in plastic case and contains the most used hole saws for pipe and entrance holes. Bi-Metal Hole Saws, Supports heavy duty cutting with its rugged constitution, which is constructed on tough metal. It needs just one pass to cut through studs. It cuts faster, smoother without as much vibration as the others due to its variable pitch teeth. Includes 2 arbors and 1 pilot drill.