SANWA Wired Ergonomic Trackball Mouse, Optical Vertical Rollerball Mice, Silent Buttons, 34mm Trackball, 600/800/1200/1600 Adjustable DPI, Compatible with MacBook, Laptop, Computer, Windows, macOS

TRACKBALL COMFORT - Equipped with a 34mm trackball, you will not need to mouse around to move the cursor as thumb controlled trackball stays in one place. Not only work on flat surfaces, but also on your leg, sofa and other surfaces as well. A full control of everything is within your fingers.
ERGONOMIC DESIGN - Places your hand in a natural wrist & arm position for smoother movement and less muscle tension. Comfortable finger rests just fit in the palm of your hand. No driver required. Once you get used to it, you will love it!
4 ADJUSTABLE DPI LEVELS - You can adjust the mouse among 4 resolutions of 600 / 800 / 1200 / 1600 DPI depending on your needs. When the count switch button is pressed, the DPI is notified by the number of flashes.
NOISELESS BUTTON - The noiseless button is mounted on the left and right clicks. Suitable for late-night PC operation, operation in quiet places such as public places, library, hospital or meetings.
WIDE COMPATIBILITY - Compatible with most system including Windows 10/ 8.1 /8/7, macOS 10.1310. 15. Fit for Notebook, PC, Laptop, Computer and other device. *Not fully compatible with Apple products.