Use the Wrench (C), Bolt (B) to secure the Cross Bar (7, 8) to the Leg (3, 4).
Use the Wrench (C), Bolt (A)(B) to secure the Legs (3,4) to the Back Frame (2) and Bolts (B),
Wrench (C) to secure the Cross Bar (7,8) to the Back Frame (2) as per diagram.
