Durable Construction: Made from premium 12.9 Carbon Steel, ensuring exceptional corrosion and heat resistance while maintaining strength in low-temperature environments. Designed for long-lasting reliability. Comprehensive Set: Features 1108 pieces, including M3, M4, M5, and M6 hex socket head cap screws in lengths of 8mm, 12mm, 16mm, and 20mm. Includes matching nuts, washers, and wrenches for convenience. Each screw adheres to precise metric specifications with minimal error. Versatile Applications: Perfect for DIY enthusiasts, professional repairs, or specialized tasks. Suitable for automotive repairs, precision machinery, electronics, toys, and 3D printing, meeting a wide variety of project requirements. Organized Storage: Packaged in a well-designed storage box with labeled compartments for easy access and sorting. Includes explanatory diagrams for seamless identification, catering to users of all experience levels. Upgrade your toolkit with this high-quality, comprehensive screw assortment for reliable performance across all your projects.