Camco TST RV Holding Tank Treatment breaks down waste and tissue and helps eliminate holding tank odors for up to 7 days. This 100% biodegradable formula contains no harmful formaldehyde. Original concentrated formula takes only 4 ounces to treat an entire 40-gallon tank in any season. Safe for all septic tanks.• Eliminates odors and lubricates sensors in your RV holding tank• Safe for all septic tanks• RV and marine approved• Non-formaldehyde• 4 ounces treat 40-gallon waste holding tank• 1 gallon bottle holds 32 treatments 100% biodegradable formula contains no formaldehyde Safe for all septic tanks Takes only 4 ounces to treat an entire 40-gallon tank | TST RV Holding Tank Treatment, Gallon