Ford Mercury Villager 1997 Owner's Manual page 186

NOTE: If your vehicle is equipped with the optional
two-passenger bench seat with built-in child seats, the
head restraints on the two-passenger bench seat are
not adjustable.
The adjustable head restraint
It is not necessary to remove the head restraints from the seats when
removing seats from the vehicle. However, you can remove the
head restraints by pressing the adjustment button at the base of the
head restraint and pulling the head restraint upward.
Remember to replace them when the seat is re-installed.
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