The CMIIM3943 from Quantic Corry is a RF & Microwave Isolator with Frequency 3.9 to 4.3 GHz, Bandwidth 400 MHz, Average Power Forward 30 W, Average Power Reverse 3 W, Insertion Loss 0.4 dB. Tags: Surface Mount, Microstrip Isolator. More details for CMIIM3943 can be seen below.