Advantage II for Dogs 12 Month Supply 11 20lb Size:One Size or with both front and or with both front and rear sections for dogs that need more assistance Horse: 1" wide Advantage II Dog: 12 Month Supply This once a month topical treatment for fleas and lice on dogs and puppies seven weeks and older features a new formula with insect growth regulatory (IGR) to kill all life stages of fleas and contains Imidacloprid preventing fleas on treated pets from infesting your home Kills adult fleas already on a pet within 12 hours and re infesting fleas within two hours Waterproof Fast and easy dermal application Only one application a month necessary Safe for puppies (7 weeks old) and dogs Item Specifications: Application: Apply entire contents of tube on the dog's back between the shoulder blades