A new standard of comfort and precision. Logitech's most advanced trackball for trackball enthusiasts and and consumers searching for alternatives to mice and touchpads. Delivers 20% less muscular strain compared to a regular mouse. A unique adjustable hinge plus extra 10° wedge offer customized comfort - choose the best angle for you between 0°, 20° and 30°. Precision mode button allows to instantly switch between speed and precise tracking. Easy-Switch™ and FLOW-enabled for effortless multi-computer workflow. Pair up to 2 computers and easily switch between them, copy and paste text, images and files. 1 Long-lasting and fast rechargeable battery: up to 4 months on a full charge and one minute of charge gives up to one full day of use.2 Connect using the included Logitech® Unifying™ receiver or via Bluetooth®. \n\n1 Requires Logitech® Options™ software, available for download at logitech.com/options. \n2 Battery life may vary based on user and computing conditions.