TST MAX RV Toilet Treatments help control unwanted odors and break down waste and tissue in your black water holding tank. The easy-to-use toilet treatments contain a special chemical that helps break down waste. A blend of citrus-scented surfactant oils trap unwanted odors in your tank, making your camping experience more enjoyable. The toilet treatments are RV and marine-approved, non-formaldehyde, and safe for all septic tanks. They're even great for portable camping toilets. One drop-in treats up to 40 gallons.• Extra-strength formula eliminates odors for up to 7 days• Helps break down waste in the RV holding tank• One drop-in treats up to 40 gallons• Does not contain toxic, formaldehyde-releasing ingredient bronopol• RV and marine-approved• Safe for all septic tanks• 15 drop-ins per bag Biodegradable and environmentally safe Stops odors for up to 7 days 15 drop-ins per bag | TST MAX RV Toilet Treatment, Citrus Scent, 15 Drop-Ins in Black