These custom 1"-8 grade 5 serrated hex flange nuts were produced at approximately 27,000 pieces, with zinc clear finish per ASTM B633 Type III. Full certs were provided with the parts to document surface and core hardness, material chemical properties, proof load, and certificate of conformance. 3rd party lab testing was also procured to confirm all factory documentation. The nuts were required to pass a 72,000 psi min proof load requirement and core hardness of 32 Rc max. Outside diameter was set at 1.95"-2.00" and overall nut height at .700"-.730".