SENTRY Calming Collar for Dogs, Lavender Chamomile Fragrance, 1 Collar For more than a decade, SENTRY has worked side by side with leading pet experts and top universities researching effective ways to help pets lead happier, less stressful lives and to strengthen their bonds with their owners. Dogs and puppies can(ft)t talk, so the way they show they are scared, frustrated, or not feeling well is to change their behavior like excessive barking, inappropriate marking, destructive behavior, and being anti-social. SENTRY Calming Collar for Dogs quickly releases a pheromone through an easy to slip on collar that helps alleviate problem behaviors triggered by travel, thunderstorms, new visitors in the home, and even introducing a new pet into the family. The collar will continue to release a calming pheromone for your dog for up to 30 days. Good behavior is right around the corner with SENTRY in-home calming products.