Kills and repels both fleas and deer ticks for up to 7 months. Also kills and prevents flea eggs and flea larvae for up to 7 months， thereby stopping the flea life cycle and preventing re-infestation. Focuses the pesticide towards your pet and away from you providing full body protection. Reflects direct light for up to 450-feet for an added dimension of nighttime safety. Water-resistant. Pleasant， fresh scent. For use on dogs and puppies 6 weeks of age and older. Fits up to a 26-inch neck.