Jam Nut, Hex Type Jam Hex, Finish Black Oxide, Material Steel, Material Grade/Class Grade 5, Thread Size 1/2 In.-20, Hex Width 3/4 in, Hex Height 21/64 in, Dimensional Standards ASME B18.2.2, System of Measurement Inch, Thread Direction Right Hand, Pack Size Small Pack, Thread Type Fine, Package Quantity 25