Internal Torx, Internal Hex, External Hex, Hex, TX
AF, Metric, Imperial, Torx, SAE
5.5 mm, 3/16 ", 5/16 ", 5/8 ", 1-1/2 "
1/4, 1, 1-1/2, 2-1/2, 3/8
38.1, 19.05, 6.35, 25.4, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Oxide, Black Phosphate