Nyloc Nuts. 1/4" / 5/16" / 3/8" / 1/2" UNC Nyloc Nuts – Zinc Plated Steel (Imperial Coarse Thread Lock Nuts with Nylon Insert). Type: Nyloc Insert Lock Nut. Hex Bolts - UNC. UNC Bolts & Set Screws. Thread Type: Unified Coarse (UNC).
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