Internal Hex, Internal Torx, External Hex, TX, Hex
AF, Metric, Imperial, Torx, SAE
9/16 ", 3/16 ", 19 mm, 5/16 ", 26 mm
1/2, 1/4, 1-1/2, 3/8, 2-1/2
6.35, 19.05, 38.1, 9.53, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide