PaceMaster Silver XRC Owner's Manual page 14

6. To assemble the Backrest
STEP 6A: Install the Seat Back (103) to the
Seat Base using Bolts (108), and Flat
Washers (5), then tighten using the 6mm Allen
Wrench (118).
Washer 18х9х2.0t—4PCS(5)
Bolt M8х15—4PCS(108)
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