Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 6DF4 1266 40 S found under Filter Band Pass by Trak Microwave Corp. The National Stock Number assigned to this part is 5915016278600, and the Federal Supply Class is 5915 Filters And Networks. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 6DF4 1266 40 S.