A washer or cone or disk shape with a centrally located hole, designed to accommodate a flat or oval head screw and provide additional bearing area on the material being fastened. It may or may not have a flush flange feature.
NSN 5965-01-090-6245
NSN 5855-01-112-7725
NSN 5925-00-840-5393
NSN 5905-01-634-0595
NSN 5935-00-713-3682
NSN 5960-00-994-4452
NSN 5835-01-013-9321
NSN 5996-01-233-1614
NSN 5835-01-550-1577
NSN 5925-00-612-7159
NSN 5920-01-217-4023
NSN 6110-01-338-6033