The C1-B66 from RD Microwaves is a Directional Coupler with Frequency 800 MHz to 1 GHz, Coupling 50 dB, Coupling Variation ±0.5 dB, Directivity 25 to 30 dB, Average Power 500 W. Tags: Module with Connectors. More details for C1-B66 can be seen below.