The 4203-6 from Narda-MITEQ is a Directional Coupler with Frequency 2 to 18 GHz, Coupling 6 dB, Coupling Variation ±1 dB, Frequency Sensitivity ±0.5 dB, Directivity 12 to 15 dB. Tags: Module with Connectors. More details for 4203-6 can be seen below.