Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number SK4-5-79R1B4 found under Coupler Directional by Spx Corporation. The National Stock Number assigned to this part is 5985011046692, 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 SK4-5-79R1B4.