Internal Hex, External Hex, Internal Torx, Hex, TX
AF, Imperial, Metric, Torx, SAE
3/16 ", 11 mm, 9/16 ", 26 mm, 33 mm
1/4, 1-1/2, 2-1/2, 3/8, 3/4
6.35, 12.5, 19.05, 38.1, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide