The MM-BDC-040180-20 from Mountain Microwave Technology is a Directional Coupler with Frequency 4 to 18 GHz, Coupling 20 dB, Coupling Variation ±1.0 dB, Directivity 12 dB, Average Power 30 W. Tags: Module with Connectors. More details for MM-BDC-040180-20 can be seen below.