He has been using a diff racket painted to look like duora since forever accordin to some close up shots of his racket. And cai yun during an interview has said it before, the racket pros use is different in specs to the ones regular consumers have access to in shops. A lot only buy them for the name and endorsement.
He's using a zf1 3u G4 repainted to look like duora 10. If you're interested in the real deal used by him just get a used z force 1. Mind you it's far from an easy racket to wield.
I have two Duora 10: (1) Duora 10 2017 new color black based with orange-blue, (2) Duora 10 LCW Limited Edition frosty blue/matte blue based with red-white. Overall, the second one feel stiffer and slight headheavier, better smash power, but little bit slower. So, it's better for single and back court area while playing double. Netting area, the first one is better feedback and great for double especially in the front court area.