VicTec 2.4GHz Wireless Optical Mouse Computer Mice with Nano Receiver, 6 Buttons, 15 Months Battery Life, 2400 DPI 5 Adjustable Levels (Black) 2.4GHz wireless transmission: A more secure and precise experience than the traditional FM radio system with an increased working distance of up to 15m No need any driver, plug and play. 5 DPI switch ( 800, 1200, 1600, 2000, 2400 ) to change the speed of mouse freely. Ergonomic design: Contoured shape and textured rubber grips keep your hand comfortable even after long hours, USB Nano Receiver which can be stored within the back of the mouse Long battery life and auto energy-saving sleeping mode: Up to 15 months of battery life virtually eliminates the need to change batteries. Battery life may vary based on user and computing conditions. The Auto Switch Off function will help you save energy as your Wireless Mouse will switch off when your PC is turned off or the receiver is disconnected Compatible with most system including Windows, Mac and Linux; Reliable wireless connection with Nano-receiver that can stay in your laptop