Read the page on Magic mouse apple.com
— Mac computer with Bluetooth wireless technology
— Mac OS X v10.5.8 or later with Wireless Mouse Software Update 1.0* or Mac OS X v10.6.1 or later with Wireless Mouse Software Update 1.0
— Existing keyboard and mouse for setup
— Two AA batteries (included)
\r* Momentum scrolling supported only on Mac OS X v10.6 Snow Leopard.