Yankee Candle Sleep Diffuser and Refills create a relaxing atmosphere for great sleep! Select from three fragrances, each specially blended with ingredients known for their calming properties, such as lavender, eucalyptus and cedarwood. Simply insert the refill directly into the diffuser - there's no water to add - and enjoy 30 nights of relaxing fragrance*. Set the diffuser's timer for two, four, or eight hours of soothing ambiance, at the fragrance intensity you find the most restful. Sleep good, feel good with the new Yankee Candle Sleep Diffuser and Sleep Diffuser Refills. *Based on eight hours of use on lowest intensity setting