The ZNDC-18-2G-S+ from Mini Circuits is a Directional Coupler with Frequency 800 to 2000 MHz, Coupling 18.0 to 18.5 dB, Coupling Variation ±0.5 dB, Directivity 14 to 25 dB, Average Power 3 W. Tags: Module with Connectors. More details for ZNDC-18-2G-S+ can be seen below.