Lock Nut, Finish Zinc Yellow, Material Steel, Material Grade/Class Grade 8, Thread Size 5/16 In.-18, Hex Width 1/2 in, Hex Height 11/32 in, Lock Type Nylon Insert, Dimensional Standards ASME B18.16.6, System of Measurement Inch, Hex Type Standard Hex, Thread Direction Right Hand, Pack Size Small Pack, Rockwell Hardness HRC24 - C32, Package Quantity 100