The JCD12K1T12K8G1-B from JQL Electronics is a RF & Microwave Circulator with Frequency 12.1 to 12.8 GHz, Average Power Forward 10 W, Insertion Loss 0.5 dB, Isolation 20 dB, Operating Temperature -40 to 75 Degree C. Tags: Drop-in Circulator. More details for JCD12K1T12K8G1-B can be seen below.