Thumb Screw Grip Style Smooth Type Thumb Screw Finish Zinc Plated Material Iron Thread Size 1/4 In.-20 Fastener Length 2 1/2 in Thread Style Fully Threaded Thread Length 2 1/2 in Head Width 1.25 in Head Height 0.813 in Tensile Strength 50 000 psi Head Type Wing Maximum Head Height 0.813 in System of Measurement Inch Head Material Iron Head Shape Wing Package Quantity 25