Welding nut is a nut fixed to the workpiece by welding. Common types include projection welding nut (DIN929) and spot welding nut (DIN2527). Its structure includes threaded section and welding base. The welding base has a boss or plane to enhance the welding strength.

High-strength blackened nuts are nuts that form a black Fe₃O₄ oxide film on the surface of alloy steel through chemical oxidation (blackening treatment). The base material is usually 42CrMo or 65 manganese steel. After quenching + tempering treatment, the hardness can reach HRC35-45.

Anti-loosening nut is a nut that prevents the nut from loosening through special design.

Colored zinc-plated nuts are passivated on the basis of electrogalvanizing to form a rainbow-colored passivation film (containing trivalent chromium or hexavalent chromium) with a film thickness of about 0.5-1μm. Its anti-corrosion performance is significantly better than ordinary electrogalvanizing, and the surface color is bright, with both functionality and decorativeness.

Electrogalvanized nuts are the most common standard nuts. A zinc layer is deposited on the surface of carbon steel through an electrolytic process. The surface is silvery white or bluish white, and has both anti-corrosion and decorative functions. Its structure includes a hexagonal head, a threaded section, and a galvanized layer, which complies with GB/T 6170 and other standards.

Electroplated galvanized flange nut is a special nut with a circular flange added to one end of the hexagonal nut. The flange increases the contact area with the connected parts, disperses the pressure and enhances the shear resistance. Its structure includes threaded section, flange and galvanized layer. Some models have anti-slip teeth on the surface of the flange (such as DIN6923 standard).