The SMC-4244 from Sierra Microwave Technology is a RF & Microwave Circulator with Frequency 4.2 to 4.4 GHz, Average Power Reverse 2 to 150 W, Insertion Loss 0.3 dB, Isolation 23 dB, Operating Temperature -20 to 65 Degree C. Tags: Coaxial Circulator. More details for SMC-4244 can be seen below.