Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 590-0003 found under by Signal Switch Co. The National Stock Number assigned to this part is 5985010316975, and the Federal Supply Class is 5985 Antennas Waveguides And Related Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 590-0003.