Washers distribute the load of a threaded fastener. They can also be used as spacers, springs, shims, locking devices, for reinforcing, and to reduce vibration.
When choosing a washer, the first consideration is type. What is the washer’s purpose? If it needs to… Learn More
Next consider what kind of material the washer should be made of. Some metals are corrosion resistant, while plastics resist chemicals and rubber washers resist vibration. Washers can help prevent galvanic corrosion, for example, insulating steel screws from aluminum surfaces. Washers are also available in felt and rubber.
Washers can be measured in inches or in millimeters, and typically have an outer diameter about twice as large as the inner diameter.