The FSOI-20-3-5-A from AGILTRON is a Fiber Optic Isolator with Insertion Loss 0.5 dB, Isolation 50 dB, Operating Temperature -5 to 65 Degree C, Optical Power 50 W/cm2, Storage Temperature -40 to 85 Degree C. More details for FSOI-20-3-5-A can be seen below.