Duramaxx BigBig Box Manual page 11

Step 3
Remove the locknut and washer from the axle (9).
Insert the axle (9) through the hub of each 305 mm (16") wheel
(3). Refit the washer to the axle (9), then tighten the locknut.
Ensure that each locknut is correctly tightened. Check the lock-
nuts at regular intervals for correct tightness.
Step 4
Join the tow bar to the handle element (4) and intermediate
section (5). Use the 5.5 cm M8 screw (15) for this purpose.
Now fit the assembled tow bar (4+5) to the frame (2). Use the
two 6 cm-long M8 screws (14) for this purpose.
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