The T1BJ4 from Sonoma Scientific is a RF & Microwave Isolator with Frequency 1.85 to 2.05 GHz, Insertion Loss 0.5 dB, Isolation 22 dB, Operating Temperature 0 to 25 Degree C. Tags: Module with Connectors, Coaxial Isolator. More details for T1BJ4 can be seen below.