The T-121S15 from Mercury Systems is a RF & Microwave Isolator with Frequency 21.2 to 23.6 GHz, Bandwidth 2400 MHz, Average Power 0.5 W, Average Power Forward 0.5 W, Peak Power Forward 2 W. Tags: Module with Connector, Coaxial Isolator. More details for T-121S15 can be seen below.