The T3ZD1 from Sonoma Scientific is a RF & Microwave Isolator with Frequency 3.6 to 4.2 GHz, Average Power 2 W, Average Power Forward 2 W, Insertion Loss 0.4 dB, Isolation 20 dB. Tags: Module with Connectors, Coaxial Isolator. More details for T3ZD1 can be seen below.