The QSDC-4000-18000-K3 from Qualwave is a Directional Coupler with Frequency 4000 to 18000 MHz, Coupling 30±1.5 to 40±1.5 dB, Directivity 6 to 10 dB, Average Power 300 W, Insertion Loss 0.9 dB. Tags: Module with Connectors. More details for QSDC-4000-18000-K3 can be seen below.