This is a set of 1/4 BSW (British Standard Whitworth) Hank Rivet Bush nuts, made from plated brass. They are available in the following sizes, types & finishes Plated brass Round, unserrated spigot & face 0.565 in (14.36 mm) 0.370 in (9.41 mm) 0.315 in (8.01 mm) 0.207 in (5.25 mm).
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