Logitech Unifying receiver
USB wireless receiver
The Logitech Unifying Receiver is a small dedicated USB wireless receiver, based on the nRF24L-family of RF devices, that allows up to six compatible Logitech human interface devices (such as mice, trackballs, touchpads, and keyboards; headphones are not compatible) to be linked to the same computer using 2.4 GHz band radio communication....