Fall asleep easier, wake up refreshed! Sleep machine features 6 natural, high-quality sounds to lull you into slumber: rain, brook, ocean, thunder, white noise and summer night. Optional sleep timer can be set for 15, 30 or 60 minutes. Portable design is great for traveling, too! Powered by AC adapter or 3 AA batteries, not included. Plastic. 4-3/8”W x 2-5/8”H x 4”D.