Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NAS121B125 found under Knob by Satair A S. The National Stock Number assigned to this part is 5355006679155, and the Federal Supply Class is 5355 Knobs And Pointers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like NAS121B125.