Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B1978 found under Relay Thermal by Jettron Products Inc. The National Stock Number assigned to this part is 5945009952221, 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 B1978.