Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 845-1889550 PC 47 found under Retainer Ring Valve by Electric Boat Corporation. The National Stock Number assigned to this part is 4820011298557, 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 845-1889550 PC 47.