2.4 GHz Wireless Keyboard and Mouse Combination (Full Size Silver) Two AA + two AAA batteries are required. Batteries need to be purchased by themselves. Purchase high-quality alkaline batteries to power keyboards and mice. Poor batteries may affect service life. Low-decibel typing and almost silent clicks will not interfere with the people around you. No wires and compact appearance keep your workspace neat. Connecting keyboard and mouse requires only one nano receiver, Plug and Play, and no software needs to be installed. Environmental-friendly ABS material, unique hidden bracket design, dust-proof effect is better. The mouse has three adjustable DPI levels to provide accurate tracking according to your habits. Long time inactivity will automatically enter the sleep mode, click any key to wake up, more power-saving. Some multimedia hotkeys (F1 and F8-F12) are not suitable for Macs. When using multimedia hotkeys, hold down [FN] at the same time. When the keyboard and mouse do not respond. 1. Turn off the power switch and remove the battery. 2. Reinstall the keyboard battery, unplug the USB receiver and reinsert it. After waiting for the computer to recognise the USB receiver, press [Esc+Q] for 5 seconds and turn on the power switch. Three. Reinstall the mouse battery, unplug the USB receiver and reinsert it. After waiting for the computer to recognize the USB receiver again, move the mouse to the USB receiver, press the [wheel + right click] for 5 seconds, and turn on the power switch at the same time. If the connection fails, try the above steps again