Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, Metric, Torx, AF, SAE
13/16 ", 5/16 ", 7/8 ", 11 mm, 11/16 "
1/4, 2-1/2, 3/8, 1/2, 3/4
25.4, 19.05, 38.1, 9.53, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Oxide, Black Phosphate