Sealand Max Control Advanced formaldehyde-free formula controls holding tank odors by break down waste and toilet tissue. Dometic Max Control Advanced holding tank deodorant Long lasting treatment eliminates holding tank odors Designed to break down solid waste and tissue paper to keep tank clog free 100% biodegradable liquid Contains no formaldehyde 4 ounces treats a 40 gallon holding tank 32 ounce bottle Replaces Sealand 379114032, 379214016 and 379214032