Looking for up to 17 days of a fly free dog, pony, horse, or barn? Who isn't? Ultrashield EX is safe to use on dogs, ponies, horses, and will even work as a premise spray. It is designed to provide weatherproof, sweat-resistant fly, gnat, tick, and mosquito  protection for ups to 17 days. It also features to sunscreens that prolong its effectiveness.