J-DEAL Scroll Endurance Wireless Mouse Ergonomic Vertical USB Mouse with Adjustable Sensitivity (600/1000/1600 DPI), Removable Palm Rest & Thumb Buttons - Reduces Hand/Wrist Pain Unique ergonomic design with removable palm rest to reduce hand and wrist pain Two thumb buttons can be used for back/forward browser navigation Driver free 3-mode DPI shift:800/1200/1600DPI adjustable High-resolution optical sensor with adjustable sensitivity for accuracy and responsiveness Receiver Distance:10 meters Nano Receiver