if you want a good OTC trim protector and blackener, use
meguiars trim detailer..... it has been by far the best ive used, it even surpasses some of the more expensive stuff by other companies, goes a long way since its more a cream and not just a thin liquid film, makes it easier to apply as well since it doesnt run.... it really soaks in, and lasted on the lower trim on my car for well over 5+ washes now, the trim hasnt turned into the greyish color after all this time, im pretty impressed by it.