Targus Wireless Optical Stow-N-Go Laptop Mouse (Silver) AMW46US Wireless receiver attaches securely to the bottom of the mouse for convenient transport Scroll wheel for easy navigation through spreadsheets and web pages Conserve power with the On/Off switch triggered by the receiver for up to 6 months** of battery life; integrated indicator light informs the user when power is low; Two AA batteries are included Windows 2000, XP, Windows Vista or Mac OS X (10.1 or above), USB port required RoHS Compliant