Castle Nut Finish Black Oxide Material Steel Material Grade/Class Grade 5 Thread Size 1 1/2 In.-12 Hex Width 2 1/4 in Hex Height 27/32 in Hex Type Standard Hex Lock Type Slotted Castle Dimensional Standards ASME B18.2.2 Material Quality Standards ASME B18.2.2 SAE J995 System of Measurement Inch Thread Direction Right Hand For Pin Diameter 5/16 in Maximum Slot Width 0.46 in Minimum Slot Width 0.37 in Overall Height 27/32 in Pack Size Small Pack Package Quantity 5