The Logitech TrackMan Marble Wheel USB Wired Optical Trackball is a unique and reliable input device for computers and laptops. This trackball features a scroll wheel for added convenience, making it easier to navigate through long documents or web pages. With a maximum DPI of 400, this optical trackball offers precise and smooth cursor movement. Its gray color and sleek design make it a stylish accessory for any workspace. The wired USB connectivity ensures a stable connection for uninterrupted use. With its three buttons and optical tracking method, the Logitech TrackMan Marble Wheel is a practical and efficient choice for users looking for a comfortable and efficient pointing device.