Multi-purpose Oatey No. 11 Liquid Flux is formulated with a strong cleaning agent to remove corrosion quickly and effectively from pipe surfaces in HVAC (Heating, Ventilation & Air Conditioning) and electrical work. No need to clean oxidized copper. Lead-free and water soluble. Shelf life 1 year from manufacture date. Not for use with aluminum, stainless steel or magnesium. Do not use on electrical parts.