Nylon Flat Washer Kit contains 500 pieces of 8 different size nylon washer spacers, packed in a clear plastic box with size detail paper for easy identification, portability and storage. Used for motherboard to prevent electrical shorts between metal contacts. Intended for general use under the head of a bolt or nut to provide a smooth surface. High quality nylon flat washer assortment kit. Easy to install and durable to use. Suitable for metric screws/bolts M2, M2.5, M3, M4, M5, M6, M8. Suitable for plumbing applications and as buffers and packers during engineering tasks. Ideal for automotive, plumbing and computer hardware/piano repair, etc. Package includes: 500 pieces. 1 x Plastic Storage Box. Delivery quantity: 500 pieces/box Product color: black Product size: outer box 13 x 6.5 x 2.3 cm. M2 (5*2*1) mm outer diameter * inner diameter * thickness 100 M2.5 (5*2.5*1)mm outer diameter*inner diameter*thickness 100 M3 (6*3*1)mm outer diameter*inner diameter*thickness 100 M4 (8*4*1)mm outer diameter*inner diameter*thickness 50 M5 (10*5*1)mm outer diameter*inner diameter*thickness 50 M6 (12*6*1.2)mm outer diameter*inner diameter*thickness 50 M8 (16*8*1.5)mm outer diameter*inner diameter*thickness 40 M10 (20*10*2)mm outer diameter*inner diameter*thickness 10 Note: Manual measurement, please allow 1-3cm error.