I found the picture on the internet. As far as I know on one side the inscription is in Cyrillic, on the other side the flag has the same inscription, but in Latin. I believe that the unit is inscribed on the streamer that is attached to the flag, but I don't know this for sure.
I could only found two pictures of unit flags in use.
I think some JNA flags should be at the Belgrade Military Museum, but so far no luck in finding a picture, so, if you have some, please post it here.