E-Mark codes are an ECE safety certification mark required by many countries including Canada applied to motor vehicle parts and systems.
For lights, the mark is usually on the inside of the lens for easy identification by vehicle inspectors and police officers.
NightDriver E-Mark lights meet stringent testing and performance requirements to bear the identification mark for street legal lighting.
Below is an example of what an E-Mark looks like:
Please note that some Canadian provinces as well as the US do not recognize E-Mark standards as street legal when it comes to auxiliary driving lights.