HP Wireless Eco-Comfort Mobile Mouse Combines style and comfort for being on the move in a design Contains over 30 percent recycled plastic; energy efficient components -- single AA battery lasts up to 7 months 2 additional programmable buttons easily accessible on the top left side allow you launch applications, control sound volume, and more 4-way tilt scroll wheel allows you to navigate right and left Advanced 2.4GHz wireless technology for less interference and longer range of operation