My mid-2011 Mac Mini at Work running MacOS Catalina 10.15.1 : r/mac
Mac OS Catalina
My mid-2010 polycarbonate “Stormtrooper” MacBook! Upgrades include macOS Catalina, a 250GB SSD, 16GB RAM, MacBook Pro keyboard keys, a higher-capacity battery, and a newer wireless card / antenna setup that supports AirDrop. :