AmazonBasics B00XBC3BF0 Mode D'emploi page 10

Step 8: Press the plastic caps (B) into the arm holes to cover the bolts.
B
Caution:
For your safety, before using your chair, make sure that all of the bolts are fully tightened.
Keep the enclosed wrench and check the bolts periodically to make sure they remain securely
tightened.
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