Package Includes:340PCS Starlock Washer1PC Plastic BoxSize As Follow:60PCS:M360PCS:M460PCS:M550PCS:M650PCS:M840PCS:M1020PCS:M12Specification:Name : Internal Tooth Starlock WashersMaterial : 65Mn Metal SteelColor: BlackSize: M3, M4, M5, M6, M8, M10, M12Quantity:340 PCSFeature:1. Choose from a wide range of sizes to meet different installation needs.2. The starlock washer exerts a spring force between the fasteners head and the substrate to create more feiction and resistance to rotation.3. Made of 65Mn metal steel, it's high-quality and durable.4. It is commonly used in our daily life and in industry. We can used in machinery equipment, industrial production of shock absorption and insulation.Note:1.Please allow 1-3mm errors due to manual measurement.2.Due to light and screen setting difference, item's color may be slightly different from the pictures.