Connect the keyboard and mouse with the small Logitech Unifying USB receiver. You get a reliable - and encrypted - wireless connection with up to 10 meters range, and virtually no delays or interruptions. The keyboard does not need new batteries until after 36 months, and the mouse's battery lasts for 18 months. The keyboard is spill-proof for up to 60 ml of liquid and abrasion-proof keystrokes ensure that the text on the keys does not fade in the first keyboard