COVER PLATESpecifications Item Description The Plate, Cover (7021299) is a carbon steel punched component designed for the Piston Pump Assembly on JLG 450AJ and 450A aerial work platforms. This cover plate measures 6 inches long by 4 inches wide by 1 inch high and weighs 0. 95 pounds, with one required per machine. It serves as a protective cover within the engine system's hydraulic assembly. Skyworks is an authorized reseller of JLG parts. Make JLG Part Number