Nylon Insert Lock Nuts are also known as stop nuts. 【Sizes】#4-40, #6-32, #8-32, #10-32, 1/4"-20, 5/16"-18, 3/8"-16, 1/2"-13, total 225 pieces/8 sizes of the most commonly used stainless steel lock nuts in a plastic case, different sizes can satisfy your different needs.
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