Carriage Bolt, Inch, Neck Type Square, Basic Material Steel, Material Grade Grade A, Fastener Finish Plain, Dia./Thread Size 1/4 In.-20, Fastener Length 3 1/2 in, Fastener Thread Direction Right Hand, Fastener Thread Type UNC (Coarse), ASME B18.5, Drill Size 1/4 in, Head Dia. 0.563 in to 0.594 in, Head Height 9/64 in, Head Type Round, Square Height 0.125 in to 0.156 in, Square Width 0.245 in to 0.260 in, Tensile Strength 74,000 psi, For Use With Grade 2 Hex Nuts, Package Quantity 50