Hex Locknut Assortment, Hex Type Standard Hex, Includes Washers No, Largest Thread Size 1/2 In.-13, Lock Type Nylon Insert, Number of Nuts 150, Number of Thread Sizes 6, Number of Washers 0, Nut Finish Zinc Plated, Nut Material Steel, Nut Type Hex Lock Nut, Smallest Thread Size 1/4 In.-20, System of Measurement Inch, Thread Sizes #10-24, 1/2 In.-13, 1/4 In.-20, 1/4 In.-28, 3/8 In.-16 x 9/16 In., 5/16 In.-18