The 4245B-20 from Narda-MITEQ is a Directional Coupler with Frequency 4 to 12.4 GHz, Coupling 20 dB, Coupling Variation ±1 dB, Frequency Sensitivity ±0.5 dB, Directivity 15 dB. Tags: Module with Connectors. More details for 4245B-20 can be seen below.