Material: Made of 304 stainless steel, it has antirust performance, high strength, corrosion resistance and can be used for a long time Size: This kit includes 7 different models of M3 M4 M5 M6 M8 M10 M12 hex nut lock nut and flat washer With Storage Box:252pcs hex nuts/ lock nuts/ flat wahers of different sizes are put in the box by category, and each model has a label, which is convenient to take and use Sturdy and Serviceable: It is also resistant to corrosion and rust in harsh environment, providing a stronger connection Wide application: The set has a wide range of uses and is suitable for DIY by repairmen, amateurs, landlords, etc The set has a wide range of uses and is suitable for DIY by repairmen, amateurs, landlords, etc