The SFC2040A from Fairview Microwave is a RF & Microwave Circulator with Frequency 2 to 4 GHz, Average Power Forward 10 W, Insertion Loss 0.5 dB, Isolation 16 dB, Operating Temperature 0 to 25 Degree C. Tags: Coaxial Circulator. More details for SFC2040A can be seen below.