The Logitech TrackMan Marble gives you superior comfort - for either hand. Ambidextrous design provides long-lasting comfort for right- and left-handed people. Convenient button controls let you easily move forward and backward when you\'re surfing the Web. Click the large buttons together and use the ball for auto-scrolling. Fingertip-based control enables fast, accurate cursor movements. Patented Marble optical technology ensures smooth tracking. Left handed? Right handed? When you\'re working on your computer day and night, and you want more flexibility, the Logitech Trackman Marble will help increase your comfort level. **You\'ll enjoy all-day comfort with this ambidextrous trackball with convenient button controls.** **Ambidextrous trackball design** A trackball design with a long, broad palm area and gentle curves keeps your hand comfortable and supported all day--whether you use your right or left hand. **Stable base** Your hand stays comfortable all day long with this stay-put design. Plus, it saves you space. **Convenient button controls** Buttons let you easily move forward and backward when you\'re surfing the Web. **Fingertip-based control** You\'ll enjoy fast, accurate cursor movement with just a move of your finger. **Marble® optical technology** Our patented technology gives you smooth tracking on almost any surface so you can be productive wherever you work.