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. ExistenceStar 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. anotherHigh 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 piecesDimensions: 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, M10:2.3mmPackage Contents: M3: 60 pieces, M4: 60 pieces, M5: 60 pieces, M6: 50 pieces, M8: 50 pieces, M10: 40 pieces, M12: 20 piecesAdvantages:-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.