General description 280 Pcs Lock Washers are made from high-quality 65 manganese steel, designed to provide a secure and reliable locking mechanism for various applications. This set includes a total of 280 lock washers in 7 different sizes, all conveniently packed in a plastic box for easy storage and organization. Technical specifications Material: 65 manganese steel Quantity: 280 pcs Sizes: M3*9mm, M4*12mm, M5*12mm, M6*14mm, M8*18mm, M10*20mm, M12*25mm Plastic box dimensions: 9.5*17*2.2cm Color: Black Usage Ideal for securing bolts and screws in various DIY and home improvement projects. Provides enhanced grip and prevents loosening due to vibration. Other information Packing list: 40 x M3 Starlock washers, 40 x M4 Starlock washers, 40 x M5 Starlock washers, 50 x M6 Starlock washers, 50 x M8 Starlock washers, 40 x M10 Starlock washers, 20 x M12 Starlock washers.