Prepare 3 bolts assembly by inserting lock washer (#C), then flat
washer (#D) onto bolts (#B). Insert dowel (#F) to the middle hole of
the backrest (#1), then align seat (#2) to the holes of the backrest (#1).
Secure the holes in the diagram by using bolts (#B).
Prepare 4 bolts assembly by inserting lock washer
(#C), then flat washer (#D) onto bolts (#A). Secure
corner holes of the seat (#2) to backrest (#1) by using
bolts (#A).