The QSDC-3800-4300-50-20-N from Qualwave is a Directional Coupler with Frequency 3.8 to 4.3 GHz, Coupling 20±1 dB, Directivity 20 dB, Average Power 50 W, Insertion Loss 0.5 dB. Tags: Module with Connectors. More details for QSDC-3800-4300-50-20-N can be seen below.