Take control back from the touchpad. This wireless mouse features a 2.4ghz connection to provide reliability and on-screen maneuverability. Stay precise with three dpi options and an optical sensor to track your movement. An ergonomic design combats wrist fatigue by mimicking your natural hand shape. Just pop in some AAA batteries and plug in the usb adapter to start using your mouse right out of the box! Number of Batteries: 2 Included: 1 Owners Manual(s) Features: Battery Operated, Wireless, Ergonomic Design, Plug And Play Battery Type: Alkaline Measurements: .87 Height/Inches, 4.41 Width/Inches, 2.24 Length/Inches Base Material: 85% Plastic, 15% Metal Battery Size: Aaa Control Types: Cordless Material: Plastic Country of Origin: Imported