New and improved bedside tinnitus masker offers a total of 24 sounds. This Sound Oasis Sleep Sound Therapy System features 12 sleep/relax/wellness sounds: ocean surf, rain, stream, white noise, forest, thunderstorm, energy chimes, tranquility, alpha clouds, sleep surf, delta voyage and dream echoes. Additionally, 12 ear therapy sounds for tinnitus relief are included. This device is powered by an AC adapter (included) or 4 AA batteries (not included). An international adapter is also included for world wide use. The Sleep Enhancement Technology included gradually slows playback speed to gently lull the user to sleep. This sleep sound therapy system includes a back-lit alarm clock with sound selection, brightness control, 10 minute snooze cycle, volume control, a 3.5mm Headphone or sleep pillow jack, and a sleep timer with auto shut-off (30, 60, or 90 minutes). One year warranty.