The CU4S0401BT-831-00 from TDK is a RF & Microwave Isolator with Frequency 814 to 849 MHz, Bandwidth 35 MHz, Average Power Forward 2.5 W, Average Power Reverse 0.6 W, Insertion Loss 0.9 dB. Tags: Surface Mount, Surface Mount Isolator. More details for CU4S0401BT-831-00 can be seen below.