Key Features;Isolates cleaner from the tank water so tank parts aren t damaged by the detergents or bleach used by other in-tank cleaners;Cleanser-treated water is injected only to the bowl where it is needed so cleaner application is efficient;Surfactant-based cleaning agent reduces spread of viruses and bacteria;Toilet bowl cleaner refill For use with Flush n Sparkle toilet bowl cleaning system safe to handle without gloves. Concentrated formula delivers more than 1 000 cleaning flushes. Easy to replace. Carded.