K 9 Advantix Green is a once-a-month topical tick, and flea treatment for dogs and puppies 7 weeks of age and older. It contains imidacloprid and permethrin. It also remains effective after swimming or bathing. This is the ultimate protection for your dog! Each packet contains 6 applications providing 6 months of protection. Effective Flea & Tick Control . . . No Prescription Required! Guaranteed US EPA approved. Each package of K9 Advantix for Dogs lasts 4 to 6 months (One vial per month) Kills 98%-100% of fleas within 12 hours - helpful in dogs with Flea Allergy Dermatitis Protects against deadly Lyme Disease, spread by ticks Repels and kills mosquitos, carriers of dangerous West Nile Virus Water-resistant, easy to apply formula stays on in baths or in the rain .