Steel annular cutter, 3/4 inch diameter shank - Industry standard. Unique tooth geometry - Allows for better centering and faster cutting. Thin wall design - Enables cutters to cut faster and more efficiently by removing less material during drilling. Ejector pin extends 1/2 inch beyond tooth tip - allows for easier/faster location of pin on hole. Flute design - shorter flute design allows chips to fall freely from cutter.