Logitech M510 Wireless Computer Mouse &ndash; Comfortable Shape with USB Unifying Receiver, with Back/Forward Buttons and Side-to-Side Scrolling, Blue ERGONOMIC SHAPE - Ergonomically sculpted design and soft rubber grips conform to your right or left hand to be naturally comfortable, and the compact size makes it easy to take with you wherever you use your computerat home, at work, or anywhere else CONVENIENT CONTROLS - Back/forward buttons and side-to-side scrolling plus zoom let you do more, faster (requires free Logitech Options software) LONG BATTERY LIFE- You might forget this mouse runs on batteries with 2 years of power from two AA batteries PROGRAMMABLE CONTROLS - Configure the buttons to do exactly what you want like switching applications, opening browser windows or jump to full screen while watching videos PLUG'N'PLAY CONNECTION - Nano-sized Logitech wireless unifying receiver stays in your computer plug it in, forget it, even add compatible wireless devices without multiple USB receivers