The QDDC-4000-8000-K25-50-NS from Qualwave is a Dual Directional Coupler with Coupling 50 dB, Coupling Variation ±1 dB, Frequency 4000 to 8000 MHz, Peak Power 800 W, Average Power 250 W. Tags: Module with Connectors. More details for QDDC-4000-8000-K25-50-NS can be seen below.