The C-OS03U-20 from Teledyne Microwave Solutions is a RF & Microwave Circulator with Frequency 490 to 510 MHz, Average Power Forward 50 W, Peak Power 1000 W, Insertion Loss 0.5 dB, Isolation 20 dB. Tags: Coaxial Circulator. More details for C-OS03U-20 can be seen below.