Perpendicular (no tilt): this can only be used by children who can hold their own heads up straight and can sit upright by themselves. It is suited to mealtime and play and other active situations. Using the 3-level tilt mechanism: reducing the angle relaxes the child’s posture. Please use the angle that suits your child’s condition and the purpose of use. The three tilt angles are about 7 degrees, 13.5 degrees and 20 degrees. Children who are unable to hold up their own heads or sit upright by themselves will need to use a tilt setting. Set the chair to the appropriate angle by observing your child to see that he is not experiencing pain or discomfort, whether his pelvis is upright and stable, and that his body is not excessively tensed. *Please closely read the instruction manual and use the chair in line with your child’s age and physical condition.