Cap Nut, Profile Extra Low Crown, Material Grade/Class Not Graded, Material Brass, Finish Plain, Thread Size 5/16 In.-18, Overall Height 0.438 in, Hex Width 9/16 in, Tensile Strength 55,000 psi, Material Quality Standards ASTM B16, System of Measurement Inch, Color Brass, Pack Size Small Pack, Rockwell Hardness B78, Thread Direction Right Hand, Package Quantity 10