The 4055-20 from Narda-MITEQ is a Directional Coupler with Frequency 7.5 to 16 GHz, Coupling 20 dB, Coupling Variation ±1.25 dB, Frequency Sensitivity ±0.75 dB, Directivity 15 dB. Tags: Module with Connectors. More details for 4055-20 can be seen below.