Nu-Calgon 4207-47 Liquid Ice Machine Cleaner is a 75% phosphoric acid of the highest food-grade quality. It is fast acting yet very safe to use and it does not give off any harsh fumes. It has been formulated for removing scale deposits from ice machines and coffee urns. Because of its 75% phosphoric acid content, it is the most concentrated ice machine cleaner in the market. Please visit the Nu Calgon web site for Product Literature Downloads.