Internal Torx, External Hex, TX, Hex, External Torx
Imperial, AF, Torx, Metric, SAE
4 mm, 3/16 ", 5.5 mm, 5/16 ", 11/16 "
1/2, 1-1/2, 2-1/2, 3/8, 1/4
38.1, 9.53, 19.05, 6.35, 25.4
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide