Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 939-1 found under Diaphragm Valve Flat by Anderson H E Co Inc. The National Stock Number assigned to this part is 4820014143706, 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 939-1.