ZoGuard Plus for Cats is a cost-effective alternative to Frontline Plus, as it contains the same active ingredients and provides equivalent flea and tick protection. This product can effectively eliminate all life stages of fleas, breaking the life cycle and preventing re-infestations. Each package comes with 3 monthly doses, offering up to 12 weeks of protection. ZoGuard Plus for Cats is waterproof and can maintain its effectiveness even after being exposed to water, bathing, or sunlight. Ingredients: Fipronil.. 9.8%, S-Methoprene.. 8.80%, Other ingredients 81.40%