The 4013C-20 from Narda-MITEQ is a Directional Coupler with Frequency 2 to 4 GHz, Coupling 20 dB, Coupling Variation ±1.25 dB, Frequency Sensitivity ±0.75 dB, Directivity 22 dB. Tags: Module with Connectors. More details for 4013C-20 can be seen below.