SAE flat washers are machined to a tighter specification and have a smaller outside diameter. Flat Washer, Fits Bolt Size 7/16 in ,18-8 Stainless Steel Polished Finish, 6 PK.USS flat washers have a large, wider body.
Sheet metal screws make excellent fasteners for attaching metal hardware to wood because the fully threaded shank provides good retention in wood.. A sheet metal screw has sharp threads that cut into a material such as sheet metal, plastic, wood, hard rubber, aluminum, and other comparable compositions.