Ergonomic DesignExclusive 54° vertical angle encourages a healthy wrist and forearm posture which reduces muscle strain, so that your wrist and forearm smoother movement and less overall strain. The vertical mouse is designed for dailywork and it makes work more comfortable!Size:4.92 x 2.56 x 3.23 in.NOTE:The USB receiver is on the bottom of the mouse. 3 Different Sensitivity OptionsThe VicTsing ergonomic wireless mouse has 3 adjustable DPI options (800/1000/1600 DPI), so you can easily change the cursor speed and enjoy different scenes. High DPI can improve your ergonomic wireless mouse accuracy.