Designed with an adjustable hinge, the Logitech MX ERGO Wireless Darkfield Trackball Mouse lets you choose a natural working angle so you can be more productive while taking care of your hands.Advanced tracking and precision button let you change cursor speed and accuracy as you need, and a scroll wheel with tilt gives you instant access to shortcuts.Great for designers and anyone working with more than one screen at a time, the MX ERGO is equipped with Logitech's FLOW technology to let you switch between two devices fluidly.