Gross Weight : 57g Operation Mode : Opto-electronic Power Type : Battery Number of Buttons : 3 Number of Rollers : 1 pcs Hand Orientation : Both Hands Switch between Bluetooth-compatible and 2.4G The smart switch between Bluetooth-compatible and 2.4G ensures stable wireless transmission. You can still use your mouse regardless of USB port shortage or the loss of receiver. Smart switch between multiple devices Automatically pairs the working device. It simultaneously connects to up to 3 devices, and easily switches between them. It simplifies complicated cross-platform maneuvers and meets multi-tasking requirements. Precision on nearly every surface The high-performance laser engine enables you to use mouse on virtually any surface. Enjoy a high-speed response and unrivaled accuracy. 1300 DPI high-definition tracking engine You will enjoy responsive and smooth cursor control with the 1300 DPI high-definition optical tracking engine. 9-month battery life With Rapoo's latest energy saving technology and power switch, you can use your mouse without power interruption for up to 9 months. Silent design Noiseless right and left click button,help you create a quiet working environment.