The DC-900-427 from RF & Noise Components is a RF & Microwave Circulator with Frequency 800 MHz to 1 GHz, Average Power Forward 250 W, Insertion Loss 0.4 to 0.5 dB, Isolation 20 to 23 dB, Return Loss 20 to 23 dB. Tags: Drop-in Circulator. More details for DC-900-427 can be seen below.