Attributes . 12 pt. Standard Length 3/8" Drive: 5/16, 1/4, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16, 7/8, 15/16, 1", 1/2" Drive: 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16, 7/8" . Names