Internal Hex, Internal Torx, External Hex, Hex, TX
Metric, AF, Imperial, Torx, SAE
5.5 mm, 5/16 ", 5 mm, 3/16 ", 1-1/2 "
1-1/2, 2-1/2, 1/2, 3/8, 3/4
38.1, 25.4, 9.53, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Phosphate, Black Oxide