The 66189-103 from Micropac Industries is a Space Qualified Optocoupler with Forward Voltage 2 to 2.2 V, Isolation Voltage 500 V, Continuous Current 50 mA (Collector), On-State Collector Current 2 to 3 mA, Power Consumption 230 mW(Power Dissipation). Tags: Through Hole. More details for 66189-103 can be seen below.