Flange Nut, Material Grade/Class Not Graded, Material Steel, Finish Black Oxide, Thread Size 1/4 In.-20, Hex Width 1/2 in, Hex Height 5/16 in, Flange Diameter 5/8 in, System of Measurement Inch, Color Black, Flange Thickness 0.094 in, Hex Type Flange Nut, Overall Height 5/16 in, Pack Size Small Pack, Rockwell Hardness 85-90 Rockwell on 15N Scale, Thread Direction Right Hand