Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 171-408-0031 found under Valve Vent by Patria Land Services Oy. The National Stock Number assigned to this part is 4820121525413, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 171-408-0031.