The DC-905-428 from RF & Noise Components is a RF & Microwave Circulator with Frequency 850 to 960 MHz, Average Power Forward 250 W, Insertion Loss 0.35 to 0.4 dB, Isolation 20 to 23 dB, Return Loss 20 to 23 dB. Tags: Drop-in Circulator. More details for DC-905-428 can be seen below.