I'm assuming you're talking about vinyl/rubber moldings. If so, I found that the key was to give them a really super-thorough cleaning (for which I use APC+), then used Back to Black -- see discussion in this review on the textured bumper moldings. The B2B held up for over 2 weeks. Now, I just use Griot's Vinyl/Rubber Dressing every couple of weeks, and the chalky/whiteness has not returned.