Hardened washers F62 series NAAMS are hardened to Rc 38-45 for sizes M6 to M10. M12 and larger are set to ASTM F436M dimensional and material specifications. The inner hole of the washer ranges from 7.0 to 39.0mm and the outer hole is 12.6 to 70.1mm with a thickness of 2.7 to 3.4mm.
