Carriage Bolt, Inch, Neck Type Square, Basic Material Steel, Material Grade Grade A, Fastener Finish Zinc Plated, Dia./Thread Size 5/8 In.-11, Fastener Length 4 in, Fastener Thread Direction Right Hand, Fastener Thread Type UNC (Coarse), ASME B18.5, Drill Size 5/8 in, Head Dia. 1.219 in to 1.344 in, Head Height 21/64 in, Head Type Round, Square Height 0.313 in to 0.344 in, Square Width 0.616 in to 0.642 in, Tensile Strength 74,000 psi, For Use With Grade 2 Zinc Nuts, Package Quantity 10