Auction is for 1 heavy-duty Dewalt drill bit designed for DeWalt 3-in. self-feed drills and features a 7/16" ball groove shank for secure gripping. The bit is compatible with Black & Decker brand drills and is 16" in length. Perfect for use in home and workshop projects. The DW1640 model is a reliable and durable choice for all your drilling needs. Comes with Free Shipping Inside Contiguous U.S.