Flange nuts can be divided into two categories according to the material. The first is ordinary carbon structural steel, which is what we usually call carbon steel; the second is stainless steel. Carbon steel is divided into Q195, 08AL and alloy steel according to the carbon content and strength of the steel. Stainless steel is divided into 304, 321, 304L, 316, 316L, 317, 317L, 310S and so on.

The surface treatment of DIN6923 flange nuts is generally divided into two types: yellow zinc and zinc plated, they are cold-galvanized. For hot dip galvanizing, hex flange nut is inappropriate. This is because the residual zinc sticking to the thread after hot-dip galvanizing is not easy to remove, and the thickness of the zinc layer is uneven, which affects the fit of the parts.

A flange nut is a nut that has a wide flange at one end. This helps to distribute the pressure of the nut over the part being secured, reducing the damage of the part and making it less likely to loosen as a result of an uneven fastening surface.