Honda Prelude 1990 Online Reference Owner's Manual page 8

Seats (cont'd)
Head Restraints
The head restraints are designed to help reduce injuries due to
whiplash. They are located at the top of each front seat-back and
have several height positions. They can be adjusted by pulling up to
the recommended position. To lower them, slide the button next to
the restraint's height bar, while pushing the restraint down.
Adjust so the top of the restraint is approximately level with the
tops of your ears. That relative position may reduce injury due to
whiplash in an accident.
If a head restraint must be removed (for cleaning, fabric repair, etc.)
pull the restraint up to its highest position, then slide the button
while pulling the restraint out.
To reinstall, reverse the above procedure.
Head Restraint Angle (Si)
The angle of the head restraint
can be adjusted by pulling it
forward or pushing it back.
Do not drive the car with head restraints removed.
Do not try to adjust head restraints while driving.
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