Overall dimensions: 2 inch high x 4 inch diameter; weighs 1 lb. 10 non-repeating unique fan sounds & 10 non-repeating unique white noise sounds Multilevel adjustable volume and 60, 120, and 180 minute sleep timer Powered using USB. Can be plugged into computer or AC Adapter (included). AC adapter runs on 100 to 240 VAC Multi-band parametric EQ speaker compensatio This fan sound system is perfect for home use or travel. You can use the machine for relaxation, study and speech privacy. It also works as a personal white noise machine that ensures a great night's sleep! Choose from 10 different fan sounds or 10 different white noise sounds. all sounds have the ability to be personalized with pin-point volume control so you can select across a wide range of sound levels from whisper to extra loud. There are even two power options, AC aqnd Power USB.Serenity Health