Camco's TST Blue Enzyme RV Toilet Treatment Drop-INs contain a new enzyme complex that digests waste, tissue, fats and proteins. This treatment activates when it hits water. Just (1) Drop-IN treats up to 40-gallons and stops odors for up to 7 days. All components are biodegradable, septic safe and do not contain harmful formaldehyde, pesticides or biocides. Includes (10) Drop-INs. Fragrance: clean scent. Made proudly in the USA. Camco makes quality products for RVing, boating, camping, towing, tailgating, and grilling that help you take your passion for the outdoors to the next level.