Features 1. This flat washer set is made of high quality copper with good electrical and thermal conductivity. 2. Flat washers can distribute a load and prevent damage to the surface being fastened, and insulate the steel screws from the surface. 3. They can be used as a spacer, wear pad, preload indicating device, locking device, and to reduce vibration. 4. A flat washer is applied when the hole has a larger diameter than the fastening nut. There are many different sizes of washers in this set that you can use for different purposes. 5. This set includes many flat washers that can be used for a long time, so you don't have to run to the hardware store looking for washers. quite a time Specification Description: Washer is a thin, disc-shaped plate with a hole in the middle that is typically used to distribute the load of a threaded fastener such as a screw or nut. Other uses are as a spacer, wear pad, preload indicating device, locking device, and to reduce vibration. High-quality bolted joints require washers to prevent preload loss after torque is applied. Washers are also important for preventing galvanic corrosion, particularly when insulating steel bolts from aluminum surfaces. Features: This set of flat washers is made of high-quality copper with good electrical and thermal conductivity. Flat washers can distribute a load, prevent damage to the surface being fastened, and insulate steel bolts from the surface. It can be used as a spacer, wear pad, preload indicator device, locking device, and to reduce vibration. The flat washer is applied when the hole has a larger diameter than the fastening nut. There are many different sizes of washers in this set that you can use for different purposes. This set includes many flat washers that can be used for a long time, so you won't have to run to the hardware store looking for washers for quite some time. Specifications: Material: Copper Type: Flat Washer ID*OD*Thickness(mm) & Quantity: M5*9*1 30pcs M6*10*1 30pcs M6*12*1 20pcs M8*12*1 20pcs M8*14*1 20pcs M10*14*1 20pcs M12*16*1 20pcs M12*18*1.5 20pcs M14*18*1 20pcs Box Size: 130 x 68 x 22mm/5.12 x 2.67 x 0.86" Package Includes: 200pcs x Washers Package List NoteWasher§, Flat, Washer§, Copper, Washer§, Plain, Washer§, Metal, Washer,