Symmtrical Optical Trackball with medium sized ball and two mouse buttons

nKensington Optical Orbit Trackball Mouse, Two-Button, Black/Silver Control your cursor with a simple touch of the finger. Uses less arm movement and desk space than a conventional mouse. Features Diamond Eye optical technology for precise tracking. Resistant to dust, reducing the need for regular trackball cleaning. Connector/Port/Interface: USB; Left/Right Hand Use: Left/Right; Mouse Technology: Optical; Trackball; Wired/Wireless: Wired. Features Diamond Eye optical technology for precise tracking. Computer Mice; Input Devices; KENNSINGTON; Mouse; Orbit Optical Trackball; Trackball; Computers; Laptops; Workstations; Input; Interfaces; Scroll Manufacturer's limited five-year warranty and free technical support. Corded desktop optical trackball.