Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, Metric, Torx, AF, SAE
11/32 ", 4.5 mm, 5/16 ", 7/32 ", 7/16 "
38.1, 25.4, 19.05, 9.53, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Phosphate, Black Oxide