The MMCDC-1840-20A from Mesa Microwave is a Directional Coupler with Frequency 18 to 40 GHz, Coupling 20 dB, Coupling Variation ±1 dB, Directivity 10 to 12 dB, Average Power 20 W. Tags: Module with Connectors. More details for MMCDC-1840-20A can be seen below.