Brother MFC-J6520DW Product Safety Manual page 6

Some areas of the machine can cause injury if covers (shaded) are closed with force. Take care
when placing your hand in the areas shown in the illustrations.
When adjusting the tray size from A3, Legal or Ledger to the original size, take care not to pinch
your fingers in the gaps or slots at the bottom of the tray to avoid injury.
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