Wireless 2.4 GHz Fashionable ultra-thin design 3 buttons, Cherry Scroll wheel With NANO receiver in the battery slot, achieving wireless operation Effective distance reaches length of 20m Using Smart Power Saving design, more energy efficient. Invisible optical technology with 160ODPl Type: 2.4G Wireless optical mouse Connectivity Technology: Wireless, USB DPI: 1600DPI Rate of return: 250Hz Effective distance: 20m