The ATi20-21.5 from Narda-ATM is a RF & Microwave Isolator with Frequency 20 to 21.5 GHz, Average Power 2 W, Average Power Forward 2 W, Peak Power Forward 0.05 kW, Insertion Loss 0.3 to 0.4 dB. Tags: Module with Connector, Coaxial Isolator. More details for ATi20-21.5 can be seen below.