Upgrade your setup for all-day comfort and productivity. Upgrade to smarter scrolling, better comfort, and more productivity. The Signature M650 features SmartWheel scrolling that delivers precision or speed the moment you need it. A choice of sizes for smaller, larger and left hands means there''s a perfect fit for anyone. Seamless wireless connectivity, silent clicks, customizable side buttons, and the contoured shape keep you comfortable and productive hour after hour. SMARTWHEEL SCROLLING Make scrolling work for you with Logitech SmartWheel. Get line-by-line precision when you need to focus on the details, and scroll super fast when you just want to breeze through lengthy pages. Automatically switch modes with the flick of your finger.