Logitech M570 Guide - How to open and how to fix connection issues. : r/Trackballs
Trackball Mouse Wireless, Ergonomic Rollerball Mouse with RGB Backlit, 2.4G USB and Dual-Bluetooth Connection, Thumb Control Mouse Rechargeable for Windows Mac Android iPad Computer Laptop, Black: Amazon.co.uk: Computers & Accessories
How to Pair Logitech M570 Mouse with Unifying Receiver (Win 10) - YouTube