Perma-Cast is a dry-shake color hardener with a water-reducing wetting agent that allows it to integrate quickly and easily into the concrete surface. The color hardener can be used on either interior floors or exterior hardscapes, creating an extremely dense surface resistant to abrasion and the effects of freezing and thawing. It is available in a wide range of streak-free colors. Butterfield Color Inc. 800-282-3388.