Bluetooth Arc Touch Mouse,Wireless Foldable Mouse Without Receiver,for Notebook Laptop Tablet(Black). 【Ultra Slim and Lightweight】Portable Design, snaps flat and slips easily into a pocket or bag. Cool power switch: Flattens for portability(power off), curve to use(power on). 【Touch Ccroll Bar】2-way touch scrolling lets you scroll both vertically for smooth, intuitive navigation. (Note: Can't scroll left and right). 【Auto Sleep Mode】The mouse will fall asleep after 10 minutes no-operation, it can be waken up by clicking any button. The mouse needs two pcs 1.5V AAA dry batteries to power it(Not included in the package).It is recommended to use a new battery for power supply, if the voltage is too low, the touch bar scrolls abnormally or does not work. 【Optical Mouse】Fast tracking sensor, for smooth tracking on most surfaces, but not on glossy surfaces. Designed for use with either hand.  Bluetooth connection method description: Put in the battery, bend the mouse, press and hold the left and right buttons at the same time for a few seconds, the mouse flashes blue light, then open the computer bluetooth search link, the bluetooth name is BT3 Bluetooth pairing method: Press and hold the right button at the same time, blue light flashes after 6 seconds size：13*5.7*1.5CM