Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 985 REF NO 21 found under Diaphragm Valve Fla by Amot Controls Corporation. The National Stock Number assigned to this part is 4820014792220, 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 985 REF NO 21.