The thread is deeply stressed, strong and fast, and there is no residual burr Superstrong yet lightweight, will withstand arduous industrial use. Material: environmentally friendly material Thread material: copper Surface treatment: plastic Size description: can be made m4.m5.m6.m8 Quantity: 5 pieces Note: It does not include other things, the color is based on the first picture, and the other pictures only show the effect Due to the differences between different monitors, the picture may not reflect the actual color of the item. Due to manual measurement. Please allow deviation. Thanks!