40227 Camco Waste Holding Tank Treatment Original formula takes only 4 Ounces to treat an entire 40-Gallon tank in any season. Also available in an easy-to-use bottle with a convenient built-in reservoir for measuring. Eliminates odors and lubricates sensors. Safe for all septic tanks. For over 40 years RVers have trusted the odor-stopping power of TST™. The name TST™ still guarantees the highest quality in sanitation treatments that contain no formaldehyde are non-staining and are safe for septic tanks. 100 Percent biodegradable and environmentally safe. Eliminates Odors And Lubricates Sensors Safe For All Septic Tanks Bio/Chemical Type : Biodegradable Formaldehyde : No Deodorant : Yes Scent : Original Tank Size : 40 Gallon Unit Quantity : Single Unit Size : 1 Gallon Unit Type : Jug