The Pro Fit Ergo TB450 Trackball Mouse from Kensington features a sculpted ergonomic design, providing all-day comfort and a unique 45-degree tilt to improve your wrist and forearm alignment. Easily connect to your Windows, MacOS, iPadOS, or ChromeOS devices via USB, 2.4 GHz RF, or Bluetooth connectivity. A high-quality optical sensor accurately tracks the 34mm thumb-operated trackball, and a built-in dpi switch allows you to choose between 400, 800, 1200, or 1600 dpi for a smooth experience. A built-in trackball ejection button lets you easily remove the trackball for cleaning to help maintain accuracy and precision. Customize up to five programmable buttons for specific tasks or keyboard shortcuts via the KensingtonWorks software. Enjoy up to 18 months of battery life on a single AA battery. The basic mouse functions are plug and play and require no software or drivers to operate.