This portable misting diffuser is connected by a USB cord (included), but can be adapted to plug into a wall. With automatic shut off, this powerful ultrasonic diffuser lasts up to 4 hours of continuous operation. This little diffuser is made of BPA free plastic, measures 3.75" height and 3.5" width and puts out an impressive plume of ultrasonic, misting aromatherapy to your space. Use essential oils and distilled water only. USB adapter for plug in use not included.