The concentrated phosphoric acid based formula for effective cleaning and descaling of toilets and urinals. High active viscous formula (when mixed with water) will uniformly coat and cling to the surface for more thorough cleaning action. Regular use will help prevent limescale build-up where germs and bacteria breed. Unique thickening colour change technology. Concentrated liquid colour changes from yellow to green upon dilution with water. Supplied in 1 litre easy-dose squeeze bottle for easy dilution without the need for additional equipment.