Logitech USB Unifying Receiver Dongle for Mouse & Keyboard 910-005235 (5 Pack) - Walmart.com
Amazon.com: Logitech Unifying Receiver, 2.4 GHz Wireless Technology, USB Plug Compatible with all Logitech Unifying Devices like Wireless Mouse and Keyboard, PC / Mac / Laptop - Black : Electronics
Logitech Wireless Unifying USB Receiver Dongle for Keyboard & Mice - AAA Polymer