Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 311765-001 found under Valve Check by Imi Cornelius Inc. The National Stock Number assigned to this part is 4820011813400, 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 311765-001.