Logitech C-U0007 Unifying Receiver for Mouse and Keyboard Works with Any Logitech Product That Display The Unifying Logo (Orange Star, Connects up to 6 Devices) - Walmart.com
Why you should really, really update your Logitech wireless dongle - The Verge
Amazon.com: New Logitech Unifying USB Receiver for Mouse MX M905 M950 M505 M510 M525 M305 M310 M315 M325 M345 M705 M215 : Electronics
Logitech M185 Compact Wireless Mouse - Designed for Laptops
New Logitech Unifying USB Receiver for Mouse MX M905 M950 M505 M510 M525 M305 M310 M315 M325 M345 M705 M215 : Electronics - Amazon.com
Logitech Unifying USB Receiver for Performance Mouse MX - Newegg.com