Hex Nut, Hex Type Standard Hex, Finish Black Oxide, Material Grade/Class Grade 2, Material Steel, Thread Size 3 In.-12, Hex Width 4 1/2 in, Hex Height 2 19/32 in, Dimensional Standards ASME B18.2.2, System of Measurement Inch, Thread Direction Right Hand, Pack Size Small Pack, Removable Yes, Rockwell Hardness B68 to C32, Thread Type Fine