Logitech Unifying Receiver for Connecting Multiple Devices
Amazon.com: Logitech USB 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 MK520 Wireless Desktop - Low Profile Incurve Keys, Comfort Pa – Branden's Test Store
Logitech MK520 Wireless Keyboard Mouse Combo with Unifying
Logitech K520 Wireless Keyboard (NO RECEIVER / NO Dongle) Keyboard Only 97855066718 | eBay
Amazon.com: Logitech MK520 Wireless Keyboard and Mouse Combo — Keyboard and Mouse, Long Battery Life, Secure 2.4GHz Connectivity (Renewed) : Electronics
Logitech MK520 Complete Wireless Combo K520 Keyboard and M510 Mouse USB Unifying (920-008972) (Renewed) (920-008972-cr) - Newegg.com