Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number DFVS-40 found under Valve Foot by Allen W D Mfg Co. The National Stock Number assigned to this part is 4820013369067, 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 DFVS-40.