Made of durable nylon: Light weight, corrosion resistance, good insulation, environmentally friendly materials Intended general use: Increase the contact area of the bolt or nut with the surface of the part to prevent the surface of the part from wearing. Daily Necessary: This box of assorted round spacer washers contains 500 pcs/8 popular sizes including the most common sizes and most common ones-M2 M2.5 M3 M4 M5 M6 M8 M10 Convenient plastic storage box:Pre-classified for quick identification and loss protection.Very convenient to use. Widely used in various fields such as semiconductor, automotive, aerospace industry and interior decoration. Mainly used in electrical connections, household and commercial appliances, car, marine, generators , machinery and facilities. Package Included: M2 Nylon Flat Washer --- 2mmx5mmx1mm (ID*OD*thickness), 100pcs; M2.5 nylon flat washer --- 2.5mmx5mmx1mm (ID*OD*thickness), 100pcs; M3 nylon flat washer --- 3mmx6mmx1mm (ID*OD*thickness), 100pcs ; M4 Nylon Flat Washer --- 4mm*8mm*1mm (ID*OD*Thickness), 50pcs; M5 Nylon Flat Washer --- 5mm*10mm *1mm (ID*OD*thickness), 50pcs; M6 Nylon Flat Washer --- 6mm*12mm*1.2mm (ID*OD*thickness), 50pcs; < p>M8 nylon flat washer --- 8mm*16mm*1.4mm (ID*OD*thickness), 40pcs; M10 nylon flat washer --- 10mm*20mm*2mm (ID* OD * thickness), 10 pieces;