TeckNet Wireless Vertical Mouse, 2.4G Ergonomic Optical Mouse with 3 Adjustable DPI Levels 2000/1200/800, 6 Buttons, for Laptop, Desktop, PC, Computer, Notebook Scientific Ergonomic Design: The wireless mouse with ergonomic design encourages healthy neutral "handshake" wrist and arm positions for smoother movement and less overall strain. 2.4GHz Wireless Connectivity: Ensures reliable connection with an increased working distance of up to 33' (15m) and eliminates delays, dropouts and interference. 3 Asjustable DPI Settings: Simply press the DPI button to select your preferred cursor speed-2000/1200/800 DPI for precise and smart tracking on many surface types. Easy-to-use: Simply plug in the tiny nano receiver and start using the ergonomic mouse right away. And after pairing theres no need to re-establish pairing after a signal loss or shutdown. 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 Two AAA battery(not included). Features a battery level indicator.