Kills fleas, ticks & chewing lice. Kills ticks, including ticks that may transmit Lyme disease. Fast action. Waterproof. Lasting control. XL: Only use on dogs 89-132 lbs. Compare to Frontline brand products, contains an active ingredient fipronil (PetArmor for Dogs is not manufactured or distributed by Merial, the makers of Frontline brand products. Frontline is a registered trademark of Merial). Questions? Comments? 1-888-908-Tick (8425).