Carriage Bolt, Inch, Neck Type Square, Basic Material Steel, Material Grade Grade 5, Fastener Finish Zinc Plated, Dia./Thread Size 5/16 In.-18, Fastener Length 1 in, Fastener Thread Direction Right Hand, Fastener Thread Type UNC (Coarse), ASME B18.5, Rib Length 1 in, Drill Size 5/16 in, Head Dia. 11/16 in, Head Height 11/64 in, Head Type Carriage, Square Height 0.187 in, Square Width 0.313 in, Tensile Strength 120,000 psi, For Use With SNAPLOCS E-Track Strap Anchors