thats just the bottom of the car painted black. my car looked exactly like that about 3 months ago, except it had a blue pinstripe on it as well on the upper section of the door. originally i was going to paint my black stripe, but i've decided to leave it, because i have white wheels, the black stripe breaks up all the white just nicely and prevents the car looking monotonous. you cant really remove it because then you're left with the cutaway that the black stripe was mounted in on the bumpers, so painting is the only real option.. just make sure you get the paint you use colour matched or it will stand out and look hideous.