(Sergeant's) The Sentry Calming Diffuser releases Good Behavior pheromones into your home to provide dogs with calming sensations. Pheromone technology has been proven to modify stress-related bad behavior. Ideal for chronic stressful situations such as separation anxiety, thunderstorms, fireworks, or the addition of a new pet. Sentry Calming Diffuser plugs into wall outlet and lasts up to 30 days. Refills for diffuser may be purchased separately. Lavender chamomile fragrance.