Camco TST RV Toilet Treatment / Tabs help to break down waste and tissue. Special fragrances has been added to help control odors. This product contains no formaldehyde, and is non staining and safe for septic tanks. A bittering agent has been added to prevent accidental swallowing. Just 1 tablet will treat up to 40 gallons of water. Recommend for use in portable and RV toilets and grey water tanks. 6/pk.