The T3YH4 from Sonoma Scientific is a RF & Microwave Isolator with Frequency 3.4 to 3.9 GHz, Average Power 2 W, Average Power Forward 2 W, Insertion Loss 0.5 dB, Isolation 23 dB. Tags: Module with Connectors, Coaxial Isolator. More details for T3YH4 can be seen below.