I used 3 coats of niteshades on my tail lights, and they look completely black untill you turn the lights on or hit the brakes, than the light shines right through it, and is still a red brake light. My friends brother is a state trooper here in NY, and he started saying something about them untill I turned the lights on and the black almost dissapeared, after that he said they're fine. The light from the flash on my camera phone is enough to see through the film on it, so its not too bad