Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 520397-004N found under Electron Tube by Video Display Corporation. The National Stock Number assigned to this part is 5960011491261, 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 520397-004N.