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-hander 3 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 Two years of battery life practically eliminates the need to replace batteries. Tilt scroll function is available 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