Thumb Screw, Grip Style Smooth, Type Thumb Screw, Finish Zinc-Plated, Material Iron, Thread Size 5/16 In.-18, Fastener Length 1 in, Thread Style Fully Threaded, Thread Length Not Applicable, Head Width 1.75 in, Head Height 0.75 in, Tensile Strength 50,000 psi, Head Type Wing, Maximum Head Width 1 3/4 in, Minimum Head Width Not Applicable, Maximum Head Height 3/4 in, Minimum Head Height Not Applicable, System of Measurement Inch, Drive No Drive, Head Material Iron, Head Shape Wing