The Kensington Expert Trackball Mouse is a high-quality optical trackball mouse designed for precision and ease of use. This black mouse features side-to-side scrolling capabilities, ideal for navigating through web pages or documents with ease. With a wired connectivity option via PS/2 or USB, this mouse is suitable for a variety of computer setups. The unit includes a charger for added convenience. The trackball technology offers a unique alternative to traditional mouse designs, providing a comfortable and efficient user experience.