The ZX30-20-20BD-S+ from Mini Circuits is a Bi-Directional Coupler with Frequency 500 MHz to 2 GHz, Coupling 18.54 to 23.10 dB, Average Power 2 W, Power 0 to 2 W, Insertion Loss 0.11 to 0.25 dB. Tags: Module with Connectors. More details for ZX30-20-20BD-S+ can be seen below.