The QSDC-3500-4500-10-20-S from Qualwave is a Directional Coupler with Frequency 3500 to 4500 MHz, Coupling 20±1 dB, Directivity 20 dB, Average Power 10 W, Insertion Loss 0.5 dB. Tags: Module with Connectors. More details for QSDC-3500-4500-10-20-S can be seen below.