The DC-1748-437 from RF & Noise Components is a RF & Microwave Circulator with Frequency 1.71 to 1.78 GHz, Average Power Forward 250 W, Insertion Loss 0.25 to 0.3 dB, Isolation 20 to 23 dB, Return Loss 20 to 23 dB. Tags: Drop-in Circulator. More details for DC-1748-437 can be seen below.