NHOU protective coatings are the fastest, least expensive way to add safety and value to your vehicle—sealing out corrosives and eliminating rust. NH Oil Undercoating is a unique blend highly refined Mineral Oil,  & Green Corrosion Inhibitors that guard against rust and corrosion on all metals. It eliminates moisture and oxygen while providing a barrier against  salt, dirt and other pollutants from the metal providing long lasting protection for your vehicle. Pleasant smell.