One of the main selling points for all OnePlus phones is the extensive custom ROM community, giving the devices plenty of OS options if the stock OxygenOS software isn't satisfactory. If you've already bought a OnePlus 7T and started experimenting with it, the stock software is now available for download, in the event you mess something up and need to go back to square one.
The current factory image is for OxygenOS 10.0.3, clocking in at 2.58GB. If you ever need to go back to the factory software experience, all you have to do is flash the zip to your device. Pretty easy. You can grab the package from the link below.