Microsoft Bluetooth Wireless Laser Mouse 8000 High Definition laser technology for more precise, more responsive, and smoother tracking 2.4GHz Bluetooth with First Connect Technology so you can connect wirelessly right out of the box Four-way scrolling button with Tilt Wheel technology for greater efficiency and comfort when ripping through long documents or web pages Fully rechargeable so you save money on batteries, includes a battery-status LED indicator Runs on one AA NiMH battery, and requires a PC running Windows XP (with Service Pack 2) or Windows Vista, 45 MB free space