Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number CP9-5-4-A PIECE 19 found under Seat Valve by Dresser Industries Inc. The National Stock Number assigned to this part is 4820013835352, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like CP9-5-4-A PIECE 19.