ASTM F835 Flat Socket head cap screws have a countersunk head with a flat top surface and hexagonal recess. The ASTM F835 specification covers the requirements for quenched and tempered alloy steel hexagon flat countersunk head cap screws, having material properties for high-strength requirements. This includes certain F835 configurations often referenced when comparing an ASTM F835 grade equivalent for engineering or substitution purposes. Dimensional specifications are governed by ASME B18.3. A Flat Socket Head Cap Screw is commonly used in applications in which it is necessary to recess the head of the fastener flush with the surface.