OSPHO is a balanced formula of Phosphoric Acid, Dichromates, Wetting Agents and Extenders. Ospho is environmentally safe and non-flammable. OSPHO seals out moisture and prevents future rust from forming. OSPHO can be applied to just about any rusted or steel surface including: Vehicles, Trailers, Fences, Iron Railings, Sheet Metal, Outside Tanks, Lawn & Farm Equipment, Marin Applications and more. OSPHO is primarily used for bars-metal applications but can be used painted surfaces as long as the quality of the paint is not compromised. OSPHO isrecommended for use under oil based primares or paints. Test trial samples before using Epoxy or other paint systems. A paint job will last much longer afetr an application of OSPHO because subsequent paint coatings attach themselves so tightly that moisture and oxygen cannot attack the metal. OSPHO is water thin and therefor covers a larger area ten painrt and goes on easily. OSPHO is easily effective for exterior and interior work alike. OSPHO safely dissolves bleeding rust from many painted surfaces. For best results, use OSPHO at temperatures no lower than 36°. Excess dew and humidity may prolong drying time, cause a reoccurrence of the drying process resulting in a powdery buildup. Spray equipment should be flushed out with water after using. Clean brushes with water. Avoid spreading OSPHO on adjacent areas such as concrete, masonary and stone work as it will etch/bleach almost immediately.