Jul 12, 2016 · During testing we mpared American standard bolting washers and fender washers and several mmon bacit-plate materials, including 1/8-inch aluminum, 3/16-inch and 1/4-inch fiberglass (FRP) plate, 1/8-inch stainless steel, 1/2-inch plywood, 3/4-inch teak, and 1/2-inch Starboard (HDPE). it StarBoard Marine Board HDPE Sheets and