Once cured, Spectrum is odorless, waterproof, and extremely resistant automotive chemicals and is odor free. Spectrum will retain permanent adhesion in even the most extreme environments. Because it won't chip or crack under extreme temperatures or abuse, it can be used as an undercoating as well as an interior coating. Spectrum is also non-toxic, non flammable and has more anti corrosion and rust inhibitors that any other product onthe market.
that is what it says about spectrum, but it doesn't say that about sludge