Internal Hex, External Hex, Internal Torx, TX, Hex
AF, Imperial, Torx, SAE, Metric
9/32 ", 5.5 mm, 9/16 ", 3/8 ", 5/8 "
9.53, 6.35, 12.5, 19.05, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Phosphatized, Oxidised, Black Phosphate, Black Oxide