Nyloc Nuts. 1/4" / 5/16" / 3/8" / 7/16" / 1/2" UNF Hexagon Bolts – Zinc Plated Steel (Part Threaded with Nyloc Nuts & Washers). Includes: 1 × Bolt, 1 × Nyloc Nut, 1 × Washer. Hex Bolts - UNF. UNF Bolts & Set Screws.
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