Tamper Resistant Screw Head Type Flat Material 18-8 Stainless Steel Finish Plain Drive Spanner Thread Size 1/4 In.-20 Fastener Length 1/2 in Head Width 0.507 in Head Height 0.153 in Drive Size #14 Dimensional Standards ASME B18.6.3 Pack Size Small Type Tamper Resistant Screw Maximum Head Width 0.507 in Minimum Head Width 0.452 in System of Measurement Inch Thread Type Coarse Package Quantity 25