Pet Action Plus, Medium, Dog Flea & Tick Applicators, Specifically Formulated For Small Dogs & Puppies That Are 8 Weeks Or Older & Weigh Between 23-44 LB, Active Ingredients To Potentially Eradicate Pests Like Fleas, Ticks & Chewing Lice, Effective Against Pesky Larvae & Flea Eggs, Waterproof Combination Of S-Methoprene & Fipronil Remains Active Even After Baths & Exposure To Sunlight, Can Be Conveniently Applied To Your Pet Once A Month Or As Directed By Your Veterinary Professional.