Jam Nut, Hex Type Heavy Jam, Finish Black Oxide, Material Steel, Material Grade/Class Grade A, Thread Size 1/4 In.-20, Hex Width 1/2 in, Hex Height 11/64 in, Dimensional Standards ASME B18.2.2, System of Measurement Inch, Thread Direction Right Hand, Pack Size Small Pack, Thread Type Coarse, Package Quantity 100