Camco 41352 TST Marine Head Premium Enzyme - 16 oz Bacterial/enzyme complex that will digest waste, tissue, fats and proteins and only activates in the presence of material requiring digestion Safe for marine; enviromentally friendly and biodegradable 4 ounces treat 40 gallon holding tank 16 ounce bottles New chemistry provides a stable product with a long shelf-life that is not temperature sensitive