①. Mini small portable pocket computer mouse for travel; 3.23 * 1.97 * 1.26 inch, net weight: 1.4 oz. ②. Wireless optical mouse for laptop with USB receiver, powered by 1 * AAA battery (not included), 1600 DPI, 3 buttons. The USB receiver is placed at the bottom of the mouse; to find the location of the battery, please open the top cover gently from the back. ③. 2.4 GHz wireless transmission, the operating distance is up to 10 meters; Compatible with Windows XP, Vista, Win 7, ME, 2000, Mac, Linux and more. ④. If you do not connect, please turn off the mouse switch, lower the USB receiver, then plug in the USB receiver and turn on the mouse switch again, press the 3 buttons (left button, right button, scroll wheel) together at the same time for about 3 to 5 seconds