The ACI-20120 from Atlantic Microwave is a RF & Microwave Isolator with Frequency 3.4 to 4.2 GHz, Average Power Forward 5 W, Insertion Loss 0.4 dB, Isolation 20 dB, Operating Temperature -10 to 65 Degree C. Tags: Module with Connector, Coaxial Isolator. More details for ACI-20120 can be seen below.