DUMVOIN(TM)Wireless Finger Handheld Mouse Mice Trackball Mouse PC Laptop Desktop computer Plug and Play, easy to install Wireless and has a trackball Off table and without limitation of operational space Suitable for Tablet PC & Laptop & Desktop computer USB PORT, USB receiver is included Ideal for both laptops and desktops Place end of index or middle finger on trigger button & thumb on trackball Scrolling function can be controlled simply by your thumb USB 2.0 interface, plug and play, no software required. Easy to use - left or right hand, or cradled between both Powered by one AAA battery(Not included)