Internal Hex, Internal Torx, External Hex, Hex, TX
Imperial, AF, Torx, Metric, SAE
5/16 ", 9/16 ", 5.5 mm, 25 mm, 1-1/2 "
3/4, 1-1/2, 1/4, 1, 2-1/2
38.1, 19.05, 25.4, 6.35, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Oxide, Black Phosphate