Phosphated black structural steel nut is a nut with special surface treatment and design, which is used for locking and securing bolted or threaded connections. The nut has a side hole design, usually parallel to the threaded hole, and the purpose of the hole is to connect the nut with adjacent parts by using a specific tool (such as a pin, pin, etc.) to prevent the nut from being damaged by vibration or other damage. force and loosen.
English
