The Magic Feet simultaneously charges your Keyboard and Magic Mouse, or the Trackpad and Magic Mouse. All devices can continue to operate while being charged. The Magic Feet includes one cylindrical battery pack for either the Wireless Keyboard or the Magic Trackpad, and one battery pack for the Magic Mouse. It"s beautiful design, made of aluminum, fits perfectly among the Apple products on your desk. It is intended to sit under your monitor or iMac as a stylish complement. Easy to install, easy to use, cost-effective.