ULTIMATE ERGONOMIC COMFORT - The ergonomic design of the new Nulea trackball mouse is comfortable for all-day use. Avoid wrist and arm movement to reduce muscle soreness, helping you focus on your work to increase efficiency and creativity! Smooth Thumb Control: Easy control in every maneuver for your most detailed projects. Optical tracking technology provides extra precise cursor movement for superior accuracy, so you can easily reach where you want with less movement. In addition, the trackball is fully removable for easy cleaning. Multitasking workflow: Connect up to 3 devices and easily switch between them. Pair with Bluetooth 1 and Bluetooth 2, or simply use the USB dongle to connect. Simply press the button at the bottom of the trackball mouse to switch for your efficient multitasking work.