External Hex, Internal Torx, TX, Hex, 6-Point
Metric, AF, Torx, Imperial, SAE
5.5 mm, 1 ", 3/16 ", 9 mm, 9/16 "
1, 3/4, 1-1/2, 2-1/2, 1/2
6.35, 25.4, 19.05, 38.1, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Phosphated, Oxidised, Black Phosphate, Black Oxide