The ZFDC-10-21 from Mini Circuits is a Directional Coupler with Frequency 1 MHz to 1 GHz, Coupling 10.63 to 11.11 dB, Directivity 23.41 to 58.41 dB, Power 1 to 2 W, Average Power 1 to 2 W. Tags: Module with Connectors. More details for ZFDC-10-21 can be seen below.