Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 81-1001 found under Valve Calibrated Flow by Gas Tech Inc. The National Stock Number assigned to this part is 4820012633944, 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 81-1001.