- Complete set of 525 pieces: screws, nuts, washers, and spacers in sizes M3x10/20/30, M4x10/20/30, M5x10/20/30, and M6x10/20/40 - Made of 304 stainless steel, offering excellent corrosion resistance and long service life - Includes round head and hex head bolts, hex nuts, flat washers, and lock collars for precise installation - Durable organizer box that makes storage and quick location of each component easy - Versatile use: suitable for 3D printers, furniture, bicycles, motorcycles, industrial machinery, cars, and smart equipment - Designed to reduce pressure and friction, protecting both the parts and the screws - Compatible with standard metric, easy to install and use in DIY and repair projects