Bore small, clean holes at any angle in a variety of materials with the Milwaukee® 6-Piece 6 in universal flat boring bit Set. These premium quality flat boring bits are made of heat treated high carbon steel, so the drill points and cutting edges can be resharpened for cost savings and long life. Bore clean, fast holes at any angle in wood, plastic, plywood and Formica. These bits offer a 6 in drilling depth but can be used with a 12 in extension (48-28-3350) for extended deep hole drilling. 3/16 in shank diameter.