Battery included. Vibrating action for deep cleaning. Massaging action to stimulate gums. Attention: Brush will not work if the battery is installed incorrectly. On and off switch is located at the bottom of the brush. Proven to remove more harmful plaque than any ordinary manual toothbrush. Effectively cleans between teeth and along gumline. Helps to prevent gum disease and tooth decay. As gentle on teeth and gums as soft manual toothbrush. www.drfresh.com. Made in PRC.