Each pack contains 3 or 6 ampoules, used as a spot on treatment monthly to prevent heartworm in dogs and cats, kill fleas in dogs and cats, treat and control ear mites in dogs and cats, treat hookworm and roundworm in cats only and control sarcoptic mange in dogs only. Not for use on puppies or kittens under 6 weeks of age. Revolution® is a registered trademark of Pfizer Inc.