Features Tear Guard - Each tooth is constructed with more steel behind the cutting edge for added strength. The extra strength of the teeth along with the 8% cobalt gives extra life to the teeth allowing for increased productivity and continued hole quality. Hole Digger includes Plug Connector, a full access slot design that allows full access during plug removal. Plug Connector provides lower access into the cut for coarse material and higher towards the teeth for fine material. With multiple positions to apply leverage and better plug access, the Plug increases productivity and eliminates lost downtime between holes. For fast, tool-free hole changes, use universal quick-change arbors. For use with mild steel, stainless steel, cast iron, aluminum.