Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number QT63X 3 4 found under Drain Valve by Nibco Inc. The National Stock Number assigned to this part is 4820014654452, 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 QT63X 3 4.