High-quality material: self-locking nuts made of durable A2 V2A 201 stainless steel and nylon, hexagonal nut surface is smooth with metallic shine which has good corrosion, rust and oxidation resistance. It can also be used indoors, outdoors and in damp areas. Specification size: we offer you locking nut stainless steel 50 pieces M4, you can choose hex nut according to the screws or bolt size, and different sizes can meet your screw nut needs. Easy to use: the stainless steel locking nut is easy to install and can be easily installed in tight spaces. Torque wrench and screwdriver is enough to tighten the stop nut, it can be dismantled and used at any time. Practical functions: self-locking stainless steel nut. When used together with threaded screws and other connectors, the nylon ring deforms after locking, and the gap between the connectors at both ends is filled to prevent the screws from falling off and loosening to play a locking role. Wide application: locking nut hexagonal nut. The anti-vibration and anti-loosening performance is much higher than other anti-loosening devices that can be used on interior and exterior decoration, steel, wood, it can also be used on aviation, automotive transport machines, electrical products and various types of machines.