Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number BY39222F TFE found under Diaphragm Valve Flat by Duriron Co Inc. The National Stock Number assigned to this part is 4820011928512, 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 BY39222F TFE.