The DI-103 from MCLI is a RF & Microwave Isolator with Frequency 3.9 to 4.4 GHz, Average Power 20 W, Average Power Forward 20 W, Peak Power Forward 0.05 kW, Insertion Loss 0.6 dB. Tags: Drop-In, Drop-In Isolator. More details for DI-103 can be seen below.