The GL-T-3400-4200-20-1 from A-Info is a RF & Microwave Isolator with Frequency 3.4 to 4.2 GHz, Average Power Forward 1 W, Average Power Reverse 1 W, Insertion Loss 0.5 dB, Isolation 20 dB. Tags: Module with Connector, Coaxial Isolator. More details for GL-T-3400-4200-20-1 can be seen below.