What is a Cup Washer?

A cup washer is a small lightweight washer with a concave shape that serves as an insulative, decorative, and supportive accessory for bolts and screws. They feature a bowl-like central depression that allows for a snag-free grip when tightening a bolt or a screw head. These types of washers act as countersunk elements or surface mounts. But what are they made of? And how can you use them? Let's take a closer look. How Cup Washers Work Cup washers generally work to support, insulate or add a cosmetic finish to screws and bolts. They often include features such as electrical [...]