Fluidmaster 8100P8 Flush 'N' Sparkle Toilet Bowl Cleaning SystemThis environmentally friendly product provides cleaning solution directly into the bowl without harming the toilet tank components. Every plumber knows that there is nothing more destructive to toilet tank parts than drop in bleach tablets. The alternative is the Flush n' Sparkle Bowl Cleaning System. Flush n'Sparkle puts a cleaning solution directly into the overflow tube of the flush valve, so no chemicals ever touch the flapper or fill valve. This