Serrated Flange Hex Nut: Zinc Coated – Coarse and Fine Thread (##) Number of pieces in one pound.

The surface of the flange has serrations which displace material on the mating surface when the nut is wrenched into place, which resists loosening. Nuts are case hardened too ensure the serrations will have sufficient gripping strength. (Example 1 pound of 1/4 nuts will give you 110 pieces.)