Internal Torx, Internal Hex, External Hex, Hex, TX
AF, Imperial, Torx, SAE, Metric
5.5 mm, 5/16 ", 9/16 ", 25 mm, 23 mm
1-1/2, 3/4, 2-1/2, 1/4, 1/2
25.4, 9.53, 38.1, 19.05, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide