'Castle Nut, Nut Style Round Slotted Nut, Basic Material Low Carbon Steel, Material Grade Grade 2, Fastener Finish Zinc Plated, Fastener Thread Direction Right Hand, Dia./Thread Size 1/2 In.-13, Fastener Thread Type UNC, Width Across Flats 3/4 In., Nut Height 7/16 In., Pin Dia. 9/64 In., Slot Width 0.18 In., Slot Depth 0.29 In., Nut Standards ASTM 563, Package Quantity 25'