The 991-540590-201 from M2 Global Technology is a RF & Microwave Isolator with Frequency 5.4 to 5.9 GHz, Average Power Forward 50 W, Average Power Reverse 5 W, Insertion Loss 0.5 dB, Isolation 20 dB. Tags: Drop-In, Drop-In Isolator. More details for 991-540590-201 can be seen below.