LOGITECH ERGO M575 Bluetooth and Wireless Trackball Mouse Trackball with wireless thumb control for comfort throughout the day Specifications for technology Sensor Technology: Advanced Optical Tracking from Logitech Value nominal: 400 dpi Maximum amount: 2000 buttons There are five buttons: front/back, left/right, and scroll wheel with middle click. Click Here for Additional Information. LOGITECH ERGO M575 Bluetooth and Wireless Trackball Mouse OUR DEVOTION TO ERGONOMICS PROVEN Although working doesn't always feel great, we perform better when we're feeling better. For this reason, we established the Logitech Ergo Lab, a meticulous process for developing ergonomic goods and services that lead to better posture, reduced muscle strain, increased comfort, and an enhanced sense of wellbeing. TIPS FOR WELLNESS Useful advice and resources to improve your mood at work, whether you're at your desk, at home,