Socket Flat Head Screw, Head Type Flat, System of Measurement Inch, Drive Type Socket, Drive Size 3/16 in, Material Steel, Finish Zinc Plated, Thread Size 5/16 In.-18, Minimum Thread Length 1 in, Fastener Length 1 in, Head Height 0.198 in, Head Diameter 0.656 in, Pack Size Small Pack, Thread Style Fully Threaded, Special Features Not Applicable, Countersink Angle 82 Degrees , Dimensional Standards ASME B18.3, Flange Diameter Not Applicable, Flange Thickness Not Applicable