Advantage II Flea Treatment for Dogs and Puppies prevents, treats, and kills fleas. Advantage gives fast relief to your dog by killing 99% of all adult fleas within 12 hours of application with its powerful main ingredient, imidacloprid. One application lasts one month. Advantage II steps up the superior flea control of Advantage by adding the insect growth regulator pyriproxyfen, preventing flea larvae from growing into adulthood and reproducing, thus attacking the whole life cycle. This treatment is waterproof, so you can rest assured your dog will be protected in any situation. Advantage II is only for dogs and puppies eight weeks of age or older. Type: Spot-Ons