The grommet will remain attached to the stem of the chair when you remove the chair from the base. If this occurs, please follow detailed Scenario 1 instructions at page 2. You will not need to use the supplied grommet.
The grommet will remain in the old base. You will need to install the new grommet (supplied) into the replacement base before inserting the chair stem (please see detailed Scenario 2 instructions page 3).