Lenovo 400 Wireless Mouse, 2.4GHz Wireless Nano USB 3-Button, 1200DPI Optical Sensor: From the producer Use the 2.4 GHz USB receiver to establish a solid connection. When you're finished, dock the receiver in the mouse itself. Even after extended use, the ergonomically shaped design and robust 1200 DPI sensor reduce hand strain. provides up to 12 months of battery life and left