Halt immediately and effectively destroys an animal's initiative to be aggressive. The dog will quickly withdraw without any outcry and in most cases will refrain from a future attack against the person who has applied the repellent. The active ingredient in Halt creates a sensation of heat that will last for several minutes, after which the animal returns to normal. Produces a liquid stream up to 10 feet - used by the US Postal Service since 1966! Not for use on humans.