Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 523439 found under Stem Fluid Valve by Level 10 Industries Inc. The National Stock Number assigned to this part is 4820011431485, 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 523439.