The CU4S1001BT-1643-00 from TDK is a RF & Microwave Isolator with Frequency 1.6265 to 1.6605 GHz, Bandwidth 34 MHz, Average Power Forward 20 W, Average Power Reverse 1 W, Insertion Loss 0.6 dB. Tags: Surface Mount, Surface Mount Isolator. More details for CU4S1001BT-1643-00 can be seen below.