Placards showing the four configurations of Y-20's cargo bay: from left to right: for deploying paratroopers, for medical evacuation, for transporting cargo pallets, and for ferrying troops (divided into two levels to maximize seating area).
I still do not understand why they are still keeping WS-20 powered Y-20s hidden. We are getting so many clear shots of the J-35A. The only missing thing from this Air show has been Y-20B.