The C1-B12S-10 from RD Microwaves is a Directional Coupler with Frequency 500 MHz to 18 GHz, Coupling 10 dB, Coupling Variation ±1 dB, Directivity 15 dB, Average Power 10 to 50 W. Tags: Module with Connectors. More details for C1-B12S-10 can be seen below.