Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number WAV 870 ITEM A191 found under Valve Check by Senner Karl Inc. The National Stock Number assigned to this part is 4820013253783, 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 WAV 870 ITEM A191.