Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 18E1640-1 found under Switch Box by Fleet Readiness Center East Div Department Of Navy. The National Stock Number assigned to this part is 5930014598284, and the Federal Supply Class is 5930 Switches. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 18E1640-1.