High-quality materialThe internal teeth quick release metal washer is made of 65 manganese steel, which is strong and durable, non-deformable, wear-resistant and corrosion-resistant. Sustainable. Existence Star lock washers apply a spring force between the head and the base plate. Utility Tool Self-locking washers are ideal for quick maintenance and repairs. It exerts a spring force between the mounting head and the base plate, holding the seal to the base plate. another High friction and resistance to rotation. Various sizesLock washers are available in the 7 most common sizes. There are M3/M4/M5/M6/M8/M10/M12. You can choose different sizes according to your needs. Wide application Gaskets are widely used in many fields, such as: mechanical equipment, lawn mowers, engines, cars, trucks, trailers, toys, bicycles, RVs, boats, pumps water, furniture, etc. Package Included Fastener combo kit contains 340 black lock washers and a plastic box. Each size is stored individually in a storage box for easy selection and storage. 7 sizes of clamp washers to meet your different needs. Technical data - Product name: Lock washer -Material: 65 manganese steel - Black - Type: M3, 4, 5, 6, 8, 10, 12 - Thickness (M3, M4, M5, M6): 0.4mm Thickness (M8, M10): 0.5mm Quantity: 340 pieces Dimensions: OD x ID: M3: 9 x 2.7mm, M4: 12 x 3.8mm, M5: 12 x 4.9mm, M6: 14 x 5.9mm, M8: 18 x 7.9mm, M10: 20 x 9.3mm. , Height: M3:1.4mm, M4:1.5mm, M5:1.5mm, M6:2.1mm, M8:2.3mm, M10:2.3mm Package Contents: M3: 60 pieces, M4: 60 pieces, M5: 60 pieces, M6: 50 pieces, M8: 50 pieces, M10: 40 pieces, M12: 20 pieces Advantages: -The joints are made of 65 manganese steel, corrosion resistant and durable. - Lock washers exert a spring force between the head and the base plate, creating greater friction and resistance to rotation. -These washers come in a separate storage box, perfect for storage and retrieval. -Widely used in mechanical equipment, industrial shock absorption, bearings, machinery, etc.