Logitech K400R Wireless Keyboard and Touchpad NO USB Dongle Receiver | eBay
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 Unifying receiver - Wikipedia
Genuine Logitech Unifying Mirco Dongle Receiver USB For keyboard K400r K400plus | eBay
The new classic Logitech K400R USB Wireless Touch Keyboard Keypad - AliExpress
Logitech USB Unifying Receiver Dongle for Mouse & Keyboard 910-005235 (Two Pack) - Walmart.com
Short review: Logitech K400r vs Plexgear Mediatrack Ergo - Erik Moberg's personal homepage - photography, gadgets, DIY, and more