For use only on dogs and puppies 8 weeks and older weighing 45-88 lbs. Kills fleas, ticks, chewing lice. Prevents and controls re-infestation. Contains fipronil, the active ingredient used in Frontline Top Spot. Fast acting. Long lasting. Waterproof. Hartz First Defense is not manufactured or distributed by Merial. Frontline Top Spot is a registered trademark of Merial. Made in the USA.