The CA-18 from Marki Microwave is a Directional Coupler with Frequency DC to 18 GHz, Coupling 30 to 50 dB, Directivity 12 to 22 dB, Average Power 200 W, Insertion Loss 0.2 to 0.7 dB. Tags: Module with Connectors. More details for CA-18 can be seen below.