Logitech Unifying Receiver for Connecting Multiple Devices
Logitech Wireless Bluetooth Audio Receiver, Bluetooth Adapter for PC/Mac/Smartphone/Tablet/AV Receiver, 3.5mm Audio and RCA Outputs to Speakers, One-Push Pairing Button, UK Plug - Black/Blue : Amazon.co.uk: Electronics & Photo
Logitech USB Unifying Receiver | PLE Computers
Logitech Unifying receiver - Wikipedia
Wireless Dongle Receiver Unifying Usb Adapter For Logitech Mouse Keyboard Connect 6 Device For M505 M510 M525 M905 M950 Etc - Pc Hardware Cables & Adapters - AliExpress