Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number WG31 04 139 found under Relay Electromagnet by Insinger Machine Company The. The National Stock Number assigned to this part is 5945015139213, and the Federal Supply Class is 5945 Relays And Solenoids. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like WG31 04 139.