Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 551-003 found under Saturable Reactor by Jaidinger Mfg Co Inc. The National Stock Number assigned to this part is 5950009607616, and the Federal Supply Class is 5950 Coils And Transformers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 551-003.