External Hex, Internal Hex, Internal Torx, TX, Hex
Imperial, Torx, AF, SAE, Metric
13/16 ", 5/8 ", 9/16 ", 5 mm, 5/16 "
1, 2-1/2, 1-1/2, 1/2, 3/8
19.05, 9.53, 38.1, 12.5, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide