Internal Hex, External Hex, TX, Hex, 6-Point
Imperial, Torx, AF, Metric, SAE
3/16 ", 5.5 mm, 5/16 ", 7/16 ", 25 mm
3/4, 1/4, 2-1/2, 1/2, 3/8
38.1, 9.53, 25.4, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide