Superior Quality S2 Tool Steel Twisted prior to the heat treating process to increase torque capacity Longer shaft for added leverage Exceeds ANSI standards Color coated to resist corrosion, manganese-phosphate contact areas to resist wear Available in fractional or metric sizes Mfg: Mayhew Steel SPECS: 45052 contains 1/16, 5/64, 3/32, 1/8, 5/32, 3/16, A 1/4, 5/16, 3/8.45053 contains 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm.