Champion RV & Marine Blended Antifreeze -50 F is specifically formulated to protect and winterize all types of potable (drinking) water plumbing systems including boats, recreational vehicles, trailers and vacation homes. Guaranteed burst-proof protection down to -50F, when used full strength. Product is ready to use. Do not add water. Alcohol blend. Non-staining formula. Product is safe for brass, copper, other metals and plastic (except acetate).