Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number TB40 1-1 found under Level Prismatic Spi by Newpor Spectra Physics Ltd. The National Stock Number assigned to this part is 4920005095585, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like TB40 1-1.