This specification provides the chemical, physical and mechanical requirements for quenched and tempered bolts manufactured from steel and alloy steel, in inch and metric dimensions, in two strength grades, two types and two styles. It is intended to ensure alignment between standards with the same intended end use and to simplify the use and maintenance of structural bolt specifications.This specification also covers dimensions, product marking, materials and manufacture, test methods, testing and lot control, requirements specific to twist-off style bolts, testing specific to 150 ksi (1040 MPa) bolts, other quality assurance requirements, test reports, and packaging and package marking.