Flange Nut, Material Grade/Class Not Graded, Material Steel, Finish Black Oxide, Thread Size 5/8 In.-18, Hex Width 1 1/16 in, Hex Height 13/16 in, Flange Diameter 1 3/8 in, System of Measurement Inch, Color Black, Flange Thickness 0.188 in, Hex Type Flange Nut, Overall Height 13/16 in, Pack Size Small Pack, Rockwell Hardness 85-90 Rockwell on 15N Scale, Thread Direction Right Hand