Rejuvenate your space with the Ellia Rejuvenate Portable Diffuser. This ultrasonic aroma diffuser delivers a fine mist of natural aroma. A water-resistant design makes it great for most rooms in your home including the bathroom. A portable rechargeable lithium ion battery offers mobility and convenience. Each battery charge lasts up to 4.5 hours. An average run-time is up to 4 hours continuously or 8 hours intermittent.