How to Use: 1. Open the back of the keyboard and the of the mouse, and put the battery inside the keyboard and mouse in the direction. 2. Take out the USB receiver and insert it into the USB port of the computer device before use. Specification: Item Type: USB Keyboard Mouse Material: ABS Keyboard Specifications: Number of Keys: 75 Keys Battery: 2 x (without) Interface: 2.4G Transmission Method: Wireless Rated Voltage and Current: 3.0V / ≤ 5 mA Mouse Specifications: DPI: 1600 Number of Keys: 3 Keys Battery: 1 x AA (without) Interface: 2.4G Transmission Method: Wireless Rated Voltage and Current: 3.0V / ≤ 50 mA Package List: 1 x Keyboard 1 x Mouse 1 x Receiver 1 x User Manual Note: Shipped Without Battery