Logitech Wireless Touch Keyboard K400 with Built-In Multi-Touch Touchpad, Black (Certified Refurbished) Large (3.5-inch) touch-pad with multi-touch navigation for easier web browsing.the USB dongle that is needed for operation is located in the battery compartment of the keyboard. Once the USB dongle is inserted into the computer/laptop the computer will instantly recognize the keyboard. Media hot keys like mute, play, volume up or down for easy entertainment control. The software lets you add and remove devices that use a Unifying receiver (the keyboards use a unifying receiver). Reliable Logitech Advanced 2.4 GHz wireless connection with up to 33 ft range This Certified Refurbished product is factory refurbished, shows limited or no wear, and includes all original accessories plus a 90-day warranty Easy and comfortable typing on quiet keys with bold, easy-to-read characters