1. The flat-style design can scatter the external pressure equally, reducing the stimulation on the surface of the wound in maximum.
2. Hydra - cone style design can increase the negative pressure drainage effect in maximum.
3. Supporting pillars locate equably on the bottom, helping to reduce the percolate retention and jam.
4. The joint part connected to the drainage pipes is designed on the sucker side, totally changing the traditional position, which was on the upper side previously.