Newline offers some of the most effective and economical choices in the cleaning industry today and Hi-Test Stone Safe Alkaline Tile And Grout Cleaner is no exception to this standard. It's pretty clear at this point that Newline's Research and Development department had "Eye of the Tiger" on the loud speaker when they churned out this baby. Newline Hi-Test is safe on acid sensitive surfaces such as marble, tile, stone, grout, travertine, terrazzo, and more. It can be used for complete restoration or simple every day maintenance. It is biodegradable, low foaming, and the level of free rinsing is extreme to say the least. This is our #1 selling natural stone and tile cleaning solution by leaps and bounds.