Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 5603B found under Connector Fluid Pump by Megator Corporation. The National Stock Number assigned to this part is 4320012731375, and the Federal Supply Class is 4320 Power And Hand Pumps. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 5603B.