This specification covers the requirements for quenched and tempered alloy steel hexagon socket button (SBHCS) and flat countersunk (SFHCS) head cap screws. The screws shall be fabricated from alloy steel made to fine grain practice. The chemical composition of the screw material shall conform to the heat analysis specified. Hardness, tensile strength, yield strength, elongation, and area reduction shall be tested to meet the requirements prescribed.