JLER 2.4G Wireless Optical Mouse with DPI Switch (Black) Powered by 2xAAA battery (not included) ,ON/OFF switch Automatically power saving wireless2.4GHz reliability and performance; Works on most surfaces except glass Working range within 10 meters Smooth, rubberized grip ergonomic design 2.4GHz Wireless USB Wheel Optical Mouse Perfect for home, office or out on the road Ideal for PC and Laptop use Dynamic Shape: Well-designed, contoured shape seamlessly fits and moves with your palm.