Blue Demon offers a completely field-replaceable PDC drilling system available in four-wing from 3⅞- to 6 ¾-inch diameters, in ⅛-inch increments, and in three-wing from 6¾ to 24 inches. Blue Demon also offers five- and six-blade standard PDC bits. All Blue Demon bits are designed for use with air, water or mud. Connectors are available, threaded with box or pin connection, to fit directly on any common drill rod used with portable drilling equipment. Used in conjunction with shank and locking bowl to complete assembly.