The RFDC4M3G20 from RF-Lambda is a Directional Coupler with Frequency 400 MHz to 3 GHz, Coupling 19 to 21 dB, Frequency Sensitivity ±0.5 to ±1 dB, Directivity 20 to 23 dB, Average Power 50 W. Tags: Module with Connectors. More details for RFDC4M3G20 can be seen below.