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. Designed for Long-time UseThis ergonomic wireless mouse has more buttons than a traditional mouse. Not only can help you adjust your ergonomic vertical mouse's DPI freely, but the two buttons on the side also allow you to browse the web pages and documents faster. mouse's size is about 4.92 x 2.56 x 3.23 inch/110g, and suitable for most hand shapes and sizes.