The M-3IDC39-1 from L-TEQ Microwave Technology is a RF & Microwave Isolator with Frequency 3.55 to 4.25 GHz, Average Power Forward 1 W, Insertion Loss 0.2 to 0.3 dB, Isolation 19 to 22 dB, Operating Temperature 15 to 35 Degree C. Tags: Module with Connectors, Coaxial Isolator. More details for M-3IDC39-1 can be seen below.