Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 685021C30004-3 found under Synchro Receiver Transmitter by Electric Boat Corp. The National Stock Number assigned to this part is 5990001101153, and the Federal Supply Class is 5990 Synchros And Resolvers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 685021C30004-3.