The JCD3600T4200G2 from JQL Electronics is a RF & Microwave Circulator with Frequency 3.6 to 4.2 GHz, Average Power Forward 20 W, Insertion Loss 0.4 dB, Isolation 20 dB, Operating Temperature -40 to 75 Degree C. Tags: Drop-in Circulator. More details for JCD3600T4200G2 can be seen below.