Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B8-031-04NB 391 found under Resistor Fixed Film by Amperex Electronic Corp. The National Stock Number assigned to this part is 5905004131029, and the Federal Supply Class is 5905 Resistors. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B8-031-04NB 391.