Internal Hex, Internal Torx, External Hex, Hex, TX
Metric, Torx, AF, Imperial, SAE
9/16 ", 5/16 ", 5/8 ", 26 mm, 23 mm
1/4, 1/2, 3/4, 1-1/2, 2-1/2
9.53, 6.35, 12.5, 25.4, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide