Rubber wire through these two rows of fixing tubes connects ventilating tube of chair back and cushion wooden beads and elastic frame.

Ventilating tubes are made of galvanized steel plate, the gap between the joint of air tube and air well should be filled with incombustible materials.

"The frequency of ventilating tube insertion in the experimental group was not related to obesity, whether measured by BMI or triglyceride or total cholesterol concentration, " the authors write.