From the Manufacturer
Overview:
You take your notebook PC everywhere. That's why the Arc Mouse is designed to go with you. Expanded, it's a sturdy and comfortable full-sized mouse. Folded, it fits perfectly into your bag.

Features:

Folds for Portability
Designed for comfort, the Arc Mouse folds to 60% of its fully expanded size, with the folding motion controlling turning the mouse on and off.

Scroll Wheel
For easy navigation.

Strong Hinge
Made of metal for durability.

Micro-Transceiver
Snaps into the bottom of the mouse.

Battery status indicator
Changes color to indicate when the battery needs to be replaced.

Additional Features:
2.4 GHz wireless with up to 30-foot range
Laser tracking
4 buttons
Carrying case included

System Requirements:
Windows 7/Windows Vista/Windows XP or Mac OS X .
Powered USB port
2 AAA alkaline batteries (included)