it doesnt matter if the car is registered or not. I have a tag and registration that i can put on a car and drive any car i want. If you have the title for it, i just have to look at that just to make sure the car aint stolen, if everything is good i put the tag on the car i have the registration with me and we off to get the 240. dont matter if a cop pulls you over. we are driving the car legally i have that tag. i used it on my integra for about 3 months.