Review on 🖱️ Enhanced Ergonomic Trackball Mouse: SANWA 2.4G Wireless Optical Vertical Rollerball Mice with Silent Buttons, 34mm Trackball, Adjustable DPI, Compatible with MacBook, Laptop, PC, Windows, macOS by Angel Larson

I'm trying to use the Logitech M570 trackball on all my computers, but my new laptop only had a USB port and I didn't want to waste a Logitech dongle . This works just as well as the M570 but does not occupy a USB port. And it appears to be slightly smaller than the M570, which is great for fitting everything in a small computer bag. The only downside, as mentioned, is that it consumes batteries. Like a couple of batteries every few days if you don't flip the ON/OFF switch when not in use. My guess is that the Bluetooth radio it contains keeps trying to connect to the laptop even when it's turned off. I bought a batch of rechargeable AAA batteries and always carry a pack of 4 batteries with me. For my desktops I'm sticking with the M570, but for my laptop this seems to help.