Stiga Airoc Astro M
Sponge hardness: Max
Weight: Approximately 66-68 grams uncut
Hardness: around 45 degrees...
Notice that in 22:23 Xu Xin's backhand rubber is a Tenergy.
Stiga Airoc Astro S
Sponge Version: Max
Weight: Approximately 62-64 grams uncut
Hardness: around 45 degrees
That shows that there's some indulgency with pro players regarding the rules.
In this case the rubber was cut a few...