The CNF-3337 from Stellant Systems is a RF & Microwave Circulator with Frequency 3.3 to 3.7 GHz, Insertion Loss 0.4 to 0.8 dB, Isolation 20 to 40 dB, Operating Temperature -20 to 65 Degree C. Tags: Module with Connector, Coaxial Circulator. More details for CNF-3337 can be seen below.