The QDDC-4000-8000-K4-40-NS from Qualwave is a Dual Directional Coupler with Coupling 40 dB, Coupling Variation ±0.4 dB, Frequency 4000 to 8000 MHz, Average Power 400 W, Insertion Loss 0.3 dB. Tags: Module with Connectors. More details for QDDC-4000-8000-K4-40-NS can be seen below.