TeckNet Omni Small Portable Wireless Optical Mouse with USB Nano Receiver for Laptop Computer, 3 Adjustable DPI Levels: 2000/1500/1000 DPI You can take the wireless mouse wherever you take your laptop, thanks to its pocket-sized compact design. 2.4GHz Wireless - A more secure and precise experience than the traditional FM radio system with an increased working distance of up to 10m. TeckNet Tru-Wave technology provides precise, smart cursor control over many surface types. TeckNet Co-Link technology  after pairing theres no need to re-establish pairing after a signal loss or shutdown Tiny USB Nano style receiver plugs into your PC and can stay there. Select your preferred cursor speed; 2000/1500/1000 DPI, Plug & play - no need to install a driver. Energy Efficient: The auto power-off function switches off the mouse when the USB Nano receiver is disconnected, or the PC is switched off to give 18 months battery life from just one AA battery. Features a battery level indicator.