An acidic liquid that removes soil, rust, molds, lubricants all in a single application. Polykleen 300L has detergent properties that effectively remove ordinary light oils and other soils as well as soldering and welding fluxes. Polykleen 300L contains acidic ingredients effective in removing rust, heat scale, tarnish and other oxides. Where steel to be painted is considerably, though not deeply rusted Polykleen 300L effectively removes this rust. Because of this feature it is often possible to eliminate a separate pickling and neutralizing cycle before pre-paint. Polykleen 300L is carefully inhibited to effectively remove burnton deposits on glass molds without attack on precise metal parts.