TrekStor SurfTab theatre 13.3 Operating Instructions Manual page 21

b) Now fold the back rest bar (2) up high enough so that it
forms an angle of approx. 90° with the base area of the stand.
i
NOTE
When folding up the back rest bar, hold the front and rear
base section (4) in position with the palm of your hand if
necessary.
c) As soon as all three elements are in the required position,
tighten the locking screws by turning them in a clockwise
direction.
21 EN