Logitech MK540 Advanced Wireless Keyboard and Mouse Combo for Windows, 2.4 GHz Unifying USB-Receiver, Multimedia Hotkeys, 3-Year Battery Life, for PC, Laptop - USB Wireless RF Keyboard - Black - USB Wireless
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 for mouse and keyboard - Walmart.com
Amazon.com: Logitech 920003051 K270 Wireless Keyboard, USB Unifying Receiver, Black : Electronics
Logitech 920-004088 K360 Compact Wireless Keyboard for Windows, 2.4GHz Wireless, USB Unifying Receiver, 12 F-Keys, 3-Year Battery Life, Compatible with PC, Laptop (Glossy Black) | Exxact
Amazon.com: Logitech 920003051 K270 Wireless Keyboard, USB Unifying Receiver, Black : Electronics