Castle Nut Finish Black Oxide Material Steel Material Grade/Class Grade 5 Thread Size 1/2 In.-20 Hex Width 3/4 in Hex Height 29/64 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 9/64 in Maximum Slot Width 0.18 in Minimum Slot Width 0.15 in Overall Height 29/64 in Pack Size Small Pack Package Quantity 50