UNF & UNC IMPERIAL SERRATED FLANGE NUTS ZINC PLATED STEEL FOR USA BOLTS, SCREWS

1/4UNF ~ 28tpi ~ overall height 0.236" ~ across flats 0.438". 5/16UNC ~ 18tpi ~ overall height 0.283" ~ across flats 0.500". 5/16UNF ~ 24tpi ~ overall height 0.283" ~ across flats 0.500". 3/8UNC ~ 16tpi ~ overall height 0.347" ~ across flats 0.562".

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