Zinsser WaterTite Etch & Cleaner, 12 Oz.

WaterTite Etch and Cleaner is a sulfamic acid-based cleaning and etching solution suitable for removing efflorescence and excess mortar build-up on concrete, stone, brick, tile and galvanized metal when mixed with water. This acid solution is safer than muriatic acid. It provides a light etch (profile) to promote coating penetration and adhesion over a variety of masonry surfaces.

WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer.