Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4357948-503 found under Spring Assembly Dum by Boeing Company The. The National Stock Number assigned to this part is 2915002107734, and the Federal Supply Class is 2915 Engine Fuel System Components Aircraft And Missile Prime Movers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4357948-503.