Pro-Clean is a mild acid solution product formulated to remove stains from masonry surfaces such as brick, concrete driveways, and walkways. Pro-Clean brightens the surface to a new look as it cleans. It also removes rust and iron stains caused by iron in water, irrigation water, and leaking radiator water. Pro-Clean can also be used to remove excess mortar & efflorescence deposits. Simply spray on and wipe off! Pro-Clean works before your eyes! Pro-Clean works best when applied by a pump-up-sprayer or brush and rinsed off with a cold water pressure washer.