1. Usability: The lock washer is suitable for quick fixing and repair, by applying a spring force between the fixing head and the base body to make the washer close tightly against the base body, the bolt thread closes tightly against the nut or base thread, resulting in increased friction and rotational resistance.^ 2. High-quality material: Lock washers are made of 65 manganese steel, strong and durable, no deformation, abrasion and corrosion resistance.^ 3. Multiple sizes: Quick lock washers have 7 sizes that are most commonly used, M3 M4 M5 M6 M8 M10 M12, you can choose different sizes according to your needs.^ 4. Wide application: Fixed washers are widely used in machine equipment, lawn mowers, engines, cars, trucks, trailers, toys, bicycles, recreational vehicles, boats, pumps, furniture, etc.^ 5. Economical package: 280 pieces of black steel lock washers and a plastic box, each size is separated in a storage box for easy selection and storage. 7 sizes can meet your different needs.^