It is the inner part of the leather which gives maximum flexibility to the ball. It has a high quality cotton layer pasted over with a natural latex giving support to the synthetic leather directly. The last two layers are high quality polyester which gives a permanent support to the ball. Due to this system stitches remain intact under large pressure during the game. The shape and roundness of the balls remain the same.
Balls get a perfect bounce and go in the right direction.
The system renders it water-proof.