1/4 in to 1 in. 1/4 in, 9/32 in, 5/16 in, 11/32 in, 3/8 in, 7/16 in, 1/2 in, 9/16 in, 5/8 in, 11/16 in, 3/4 in, 13/16 in, 7/8 in, 15/16 in, 1 in. Range of Head Sizes. Not eligible for promotion.