The SMI-4450 from Sierra Microwave Technology is a RF & Microwave Isolator with Frequency 4.4 to 5 GHz, Average Power Reverse 2 W, Insertion Loss 0.3 dB, Isolation 23 dB, Operating Temperature 20 to 65 Degree C. Tags: Module with Connector, Coaxial Isolator. More details for SMI-4450 can be seen below.