Hexagon thin nut DIN 439-2 Steel Plain 04 M4

This low-profile hex nut, manufactured to DIN 439-2 and ISO 4035 standards, is made of plain steel—meaning steel without any coating or surface treatment. It's a property class 04 nut with metric threading. Designed as a thin jam nut, it features a low profile and reduced load capacity, and is intended to lock other nuts in place and prevent them from vibrating loose. Since plain steel offers virtually no corrosion resistance on its own, that's something to keep in mind depending on the application.