UNC Imperial Grade C All Metal Zinc Stover Lock Locking Nuts 1/4 5/16 3/8 1/2"

Thread - UNC. Finish - Clear Zinc Plated. Grade - Grade C (above 8.8 High Tensile Steel). 1/4 - 20Tpi, 7/16" Spanner, Nut Height = 6.4mm. 5/16 - 18Tpi, 1/2" Spanner, Nut Height = 8.1mm. 3/8 - 16Tpi, 9/16" Spanner, Nut Height = 5.1mm.

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