The QSDC-4000-18000-20 from Qualwave is a Directional Coupler with Frequency 4000 to 18000 MHz, Coupling 10±1 to 30±1 dB, Directivity 10 to 12 dB, Average Power 20 W, Insertion Loss 1 dB. Tags: Module with Connectors. More details for QSDC-4000-18000-20 can be seen below.