Kensington Orbit Trackball Mouse with Scroll Ring (K72337US)<div style="text-align: left;"><strong>[Product Information]</strong><ul><li id="replacementPartsFitmentBullet" class="aok-hidden" data-doesntfitmessage="We're not sure this item fits your " data-fitsmessage="This fits your "><span class="a-list-item"><span id="replacementPartsFitmentBulletInner"><a href="#" class="a-link-normal hsx-rpp-fitment-focus">Enter your model number</a>to make sure this fits.</span></span></li><li><span class="a-list-item"> Trackball Mouse with Scroll Ring for comfort and precision </span></li><li><span class="a-list-item"> Customizable 2-Button design via TrackballWorks software </span></li><li><span class="a-list-item"> Compatible with Windows (including Windows 8) and Mac OS Computers </span></li><li><span class="a-list-item"> Scroll ring allows fast， easy scrolling of web pages and documents </span></li><li><span class="a-list-item"> Uses far less desk space than a mouse </span></li><li><span class="a-list-item"> Optical technology for precise tracking - no cleaning required </span></li><li><span class="a-list-item"> Click-free scrolling </span></li><li><span class="a-list-item"> USB connectivity </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/41QbKfl4%2BeL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31WR6yIDl9L.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31iwNCKciBL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/41qNJamppRL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/616FwXdq6OS.png" noproxy>