Your hand can relax in comfort hour after hour with this ergonomically designed mouse. Its contoured shape with soft rubber grips gently curved sides and broad palm area give you the support you need for effortless control all day long. You ve got the control to do more faster. Flipping through photo albums and Web pages is a breeze especially for right-handers with three standard buttons plus Back/Forward buttons that you can also program to switch applications go full screen and more. And side-to-side scrolling plus zoom gives you the power to scroll horizontally and vertically through your music library maps and Facebook feeds and zoom in and out of photos and budget spreadsheets with a click.* * Requires Logitech SetPoint software (Windows ) or Logitech Control Center software (Mac OS X) available for download at www.logitech.com/downloads. Two years of battery life practically eliminates the need to replace batteries. ** The On/Off switch helps conserve power smart sleep mode extends battery life and an indicator light eliminates surprises. ** Battery life may vary based on user and computing conditions. The tiny Logitech Unifying receiver stays in your laptop. There s no need to unplug it when you move around so there s less worry of it being lost. And you can easily add compatible wireless mice and keyboards to the same wireless receiver. Laser tracking means you ll enjoy smooth responsive cursor control even on surfaces that cause problems for traditional optical mice such as polished or wood-grain tables.*** *** The laser sensor does not work on glass or mirrors.