Mouse Features Comfort for Either Hand - Use your mouse with your left or right hand-ambidextrous design makes it comfortable either way. Optical Technology - Navigate with better speed, accuracy and reliability-the optical sensor tracks movement on nearly any surface without the hassle of clogged mouse parts. Scroll Wheel - Move through your documents quickly without having to click on the on-screen scroll bar. Keyboard Features Media Center - Four hot keys let you control the most-used media activities (play/pause, volume up, volume down, and mute). Quiet-touch Keys - Quiet, responsive, thin-profile keys. Calculator Hot Key - With the touch of the button, you can quickly access the Calculator. Spill-Resistant Design - Enjoy a drink while you work-this keyboard is designed to withstand an accidental spill. Windows® Start Button - Press to launch your Start menu and search your PC or the Web if you have Windows Vista installed. Plug and Play - No software needed. Just connect the keyboard to your PC and go!