The CD4-12.4-20-30 from Analog Microwave Design is a Directional Coupler with Frequency 4 to 12.4 GHz, Coupling 20 dB, Directivity 17 dB, Average Power 30 W, Peak Power 250 W. Tags: Module with Connectors. More details for CD4-12.4-20-30 can be seen below.