The ZFDC-20-1HB-S+ from Mini Circuits is a Bi-Directional Coupler with Frequency 30 to 400 MHz, Coupling 20.58 to 20.83 dB, Average Power 25 W, Power 0 to 25 W, Insertion Loss 0.07 to 0.24 dB. Tags: Module with Connectors. More details for ZFDC-20-1HB-S+ can be seen below.