Stainless Steel Flat Washers with Black Oxide Coatingbuy on amazon
1/2", 1/4", 3/8", 5/16"
Flat washers are used with a bolt or screw to distribute the load evenly. They also protect the surface underneath when tightening a bolt or screw. These are made from superior rust resistant grade 18-8 stainless steel with a black oxide coating.