The ZX30-20-4 (+) from Mini Circuits is a Directional Coupler with Frequency 5 MHz to 1 GHz, Coupling 20.09 to 20.85 dB, Directivity 12.18 to 29.14 dB, Power 1 W, Average Power 1 W. Tags: Module with Connectors. More details for ZX30-20-4 (+) can be seen below.