Provecta Advanced Flea Tick Large Dogs 21–55 lbs 4-Month Topical ApplicationProvecta Advanced for large dogs 21 55lbs is a once a month topical application that kills and repels fleas, ticks (Brown dog ticks, American dog ticks, Lone Star ticks, and Deer ticks), lice, and mosquitoes and aids in the control of biting flies. For use on dogs seven weeks of age and older. 4 month supply. Key Points: 4 month supply for large dogs 21 55lbs Once a month topical kills & repels fleas & ticks Repels mosquitoes, lice & biting flies For