The MX ERGO Plus Wireless Trackball Mouse from Logitech is an ergonomic mouse featuring a unique adjustable hinge, which adjusts up to 20°, so you can find a more natural and comfortable hand position that suits you. Furthermore, it's got a 512 to 2048 dpi optical sensor, a 4-way scroll wheel with a middle click, and a 500mAh built-in battery that can last up to four months depending on use. Connect this mouse to your system wirelessly using the included unifying receiver or via Bluetooth technology. It can also be paired and used with two systems at the same time thanks to Logitech FLOW technology.