The CU1S1281BC-3540-00 from TDK is a RF & Microwave Circulator with Frequency 3.48 to 3.6 GHz, Bandwidth 120 MHz, Average Power Forward 20 W, Insertion Loss 0.3 dB, Isolation 20 dB. Tags: Surface Mount, Surface Mount Circulator. More details for CU1S1281BC-3540-00 can be seen below.