The de-icer is horrible stuff...totally pits any aluminum it comes in contact with after 24hrs. In Central/Eastern Wa, we've been dealing with it for almost 10 years. It'll etch wheels, frames, boats, trim, brakes, anything that has some sort of aluminum in it. Shark hide works ok, but will wear off....it just sucks. But...it keeps the guys that have pretty boats off the roads in the winter!!!!! According to the DOT it's safe for the environment.