Powder Brewery Wash (PBW) is a proprietary cleaning agent. It is widely used in the brewing industry as a general purpose cleansing agent to remove brewing residues and scale. It is a buffered detergent that is not caustic and is safe for use on nearly all surfaces including stainless steel, brass, bronze, glass and plastic. It can be used to safely remove tartrate crystals and other stains with out the danger associated with more powerful agents. Normal dose is 2 ounces per five gallons of warm water. Should be rinsed off after use.