The C-218-16 from RLC Electronics is a Directional Coupler with Frequency 2 to 18 GHz, Coupling 6 to 30 dB, Coupling Variation ±0.5 to 1 dB, Directivity 12.4 to 15 dB, Average Power 50 W. Tags: Module with Connectors. More details for C-218-16 can be seen below.