Internal Hex, External Hex, Internal Torx, TX, Hex
AF, Imperial, Torx, SAE, Metric
5/16 ", 7/32 ", 9/32 ", 12 mm, 7/16 "
1, 2-1/2, 1-1/2, 1/2, 3/8
25.4, 6.35, 19.05, 38.1, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Oxide, Black Phosphate