Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number XFMS500F found under Resistor Variable W by Sfe Technologies. The National Stock Number assigned to this part is 5905008977072, 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 XFMS500F.