（
13
）
Connect seat frame adjusting bar (N) and back frame (L) with bolts (MM), nuts (GG). (Fig13)
（
14
）
Lay the
adjustable support
of the adjusting bar (N) on the back supporter (J). (Fig14)
（
15
）
Hang one of the side of suspender (O) onto the hooks of arm left (M1) and arm right (M2). (Fig15)
Step 4:
