Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 5S4520R3 found under Impeller Pump Centrifugal by Gusher Pumps. The National Stock Number assigned to this part is 4320001038378, 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 5S4520R3.