Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, Metric, AF, Torx, SAE
7/32 ", 9/32 ", 5.5 mm, 13 mm, 5/8 "
1-1/2, 3/8, 1, 2-1/2, 1/2
38.1, 25.4, 6.35, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide