The SMC-3337 from Sierra Microwave Technology is a RF & Microwave Circulator with Frequency 3.3 to 3.7 GHz, Average Power Reverse 2 to 150 W, Insertion Loss 0.4 dB, Isolation 20 dB, Operating Temperature -20 to 65 Degree C. Tags: Coaxial Circulator. More details for SMC-3337 can be seen below.