Expert Mouse Wireless Trackball gives you the freedom to be hyperproductive without being limited by a USB cable The trackball can be paired through Bluetooth 40 LE to save a valuable USB port, or connected via USB nano receiver TrackballWorks software offers incredible customization Optical tracking technology offers smooth, precise cursor control Awardwinning Scroll Ring lets you quickly scan up and down web pages or long documents Add it all up and you get exceptional comfort and easeofuse from the brand that has set the industry standard in trackballs for more than 20 years Detachable wrist rest for hand and wrist provides ergonomic comfort Ambidextrous design works equally well for both righthanded and lefthanded users Autosleep helps conserve AA battery life