External Hex, Internal Torx, Internal Hex, TX, Hex
Imperial, Torx, Metric, AF, SAE
9/32 ", 5/16 ", 7/8 ", 11/16 ", 25 mm
1, 1-1/2, 2-1/2, 1/2, 3/8
38.1, 12.5, 6.35, 25.4, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Phosphatized, Oxidised, Black Phosphate, Black Oxide