Works fast! Starts killing fleas and ticks in as little as ONE HOUR! Prevents and controls reinfestation Fleas and ticks don’t have a chance to lay eggs, stopping the reinfestation cycle Kills newly emerged adult fleas before they can lay eggs Kills – Fleas – Ticks – Chewing Lice. Aids in the control of sarcoptic mange. Waterproof. MAXIMIZE efficacy with SENTRY FIPROGUARD MAX – Contains fipronil, the same active ingredient used in Frontline products, now only better! Creates a synergistic effect that provides unparalleled efficacy. The answer to flea resistance to fipronil. Two formulations: For dogs - Fipronil (9.8%) + Cyphenothrin (5.2%). For cats - Fipronil (9.8%) + Etofenprox (15.0%)