This specification covers the requirements for quenched and tempered alloy steel screws 1.6 mm through 48 mm in diameter having a minimum ultimate tensile strength of 1170 MPa. The screws shall be fabricated from steel made to fine grain practice and shall have an austenitic grain size of 5 or finer. In the event of controversy over grain size, referee tests on finished screws conducted in accordance with Test Methods E112 shall prevail. One or more of the following alloying elements: chromium, nickel, molybdenum, or vanadium shall be present in the steel in sufficient quantity to ensure the specified strength properties are met after oil quenching and tempering. The hardness limits shall be met anywhere on the cross section through the threads, one diameter from the screw point as determined using Test Methods F606M.