Hand Orientation: Both Hands Power Supply: 2 x AAA Batteries Operating System Supported: Windows XP, 2000, Vista Mac OS 10.4.X and higher System Requirement: USB port Features: Nano Receiver - Small enough to plug in once and leave connected. Wireless - Plug in nano receiver and go wireless. 2.4GHz reliability and performance. Nano Slot - Convenient nano receiver storage for when you need it. Comfort Grip - Smooth, contoured design allows for comfort and control. Package Contents: Mouse, Nano receiver, 2 x AAA Batteries