Cleaning up PC 3 BG of DJI *.Bak files

I have 30GB of these type files in my DJI Assistant 2 folder - PhantomEXPORT_FILE_2019-01-21_14-53-47.
There are probably 25 files and they are all .bak files. Just wondering what to use to open them. When I start DJI Assistant 2, it wants me to hook up my Phantom 4 Pro before doing anything. Tried opening one on the Airdata website, no luck. It’s an early history of my P4P flights, don’t really want to delete them but would like to know how to read them. Thanks!