LTP Grout Stain Remover is the solution for removal of cement and grout residues and is extremely effective against mineral salt formations (efflorescence). Useful for routine cleaning of patios and other outside paved areas, LTP Grout Stain Remover may be used on glazed ceramics, quarry tiles, terracotta and some stone. Pick this product if you have cement and grout residues, mineral salt formations, limescale, water marks, dirty patios and other outside areas. Do not use on limestone or when underfloor heating systems are in operation. DO NOT USE ON ACID SENSITIVE SURFACES.