Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A1-4000-ST-1 found under Cable Assembly Fiber Optic by Fiber Systems International Inc. The National Stock Number assigned to this part is 6020014838779, and the Federal Supply Class is 6020 Fiber Optic Cable Assemblies And Harnesses. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like A1-4000-ST-1.