Wireless Optical Mouse 1620 1000 DPI high-definition tracking engine You’ll enjoy responsive and smooth cursor control with the 1000 DPI high-definition tracking engine. Up to 9-month battery life With Rapoo's latest energy saving technology and power switch, you can use your mouse without power interruption for up to 9-month. Reliable 2.4GHz wireless connection Reliable 2.4GHz wireless connection with up to 10M working range. System Requirements Windows: Windows® XP/Vista/7 USB port MAC: Mac OS® X 10.4 or later USB port Size: 64mm * 111mm