Made of nylon: used for the motherboard to avoid short circuits between metal and metal. for general use under the head of a bolt or A nut to provide a smooth surface. Contains 8 most commonly used nylon washer sizes Type: M2, M2.5, M3, M4, M5, M6, M8, M10. Come with a plastic storage box: organized by type in a transparent storage case for quick access and protection . High quality nylon platform assortment kit. Quantity of package: 500 pieces. Name of the pattern: Black nylon flat washer 500 pcs Product description Nouvelle high quality copper flat washer. Material: Nylon The black color Type: M2 m2.5 m3 m4 m5 m6 m8 m10 The package includes: 100pcs M2 5 * 2 * 1mm 100pcs M2.5 5 * 2.5 * 1mm 100pcs M3 6 * 3 * 1mm 50 pcs M4 8 * 4 * 1mm 50 pcs M5 10 * 5 * 1mm 50 pcs m6 12 * 6 * 1.2mm 40pcs M8 16 * 8 * 1.4mm 10pcs M10 20 * 10 * 2mm