The RFSL3143 from RF-CI is a RF & Microwave Isolator with Frequency 285 to 325 MHz, Average Power Forward 200 W, Average Power Reverse 20 W, Peak Power Forward 1 kW, Insertion Loss 0.4 to 0.5 dB. Tags: Module with Connector, Coaxial Isolator. More details for RFSL3143 can be seen below.