Settings Metered Air Freshener Dispenser, 3.5" x 3.5" x 8.25", Black, 6/CartonSleek modern design with simplified user interface allows for easy, flexible programming to customize your fragrance experience to 7. 5, 15 or 30 min periods. Light, Dark or both light sensor setting that ensures dispenser runs only when needed. Operates efficiently for two years on four AA batteries (not included). Refills sold separately.