Hex Nut Hex Type Heavy Hex Finish Black Oxide Material Grade/Class Grade C Material Steel Thread Size 5/8 In.-11 Hex Width 1 1/16 in Hex Height 5/8 in Material Quality Standards ASTM 563 System of Measurement Inch Thread Direction Right Hand Pack Size Small Pack Removable Yes Rockwell Hardness B78 to C38 Thread Type Coarse Package Quantity 25