Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 3003 found under Shield Electron Tub by Incom Intl Inc Morse Controls Di. The National Stock Number assigned to this part is 5960002308579, and the Federal Supply Class is 5960 Electron Tubes And Associated Hardware. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 3003.