Volvo S60 Owner's Manual page 13

Seat belt and seat belt tensioner
All seat belts are equipped with seat belt
tensioners. A small mechanism, built into the
seat belt reel, triggers at the moment of impact
to tension the belt around the body and reduce
slack from clothing, etc. The belt thus restrains
the passenger more quickly.
WARNING
If the seat belt has been subject to excessive
stress, such as during a collision, the entire
seat belt assembly including the reel,
mountings, bolts and lock must be replaced.
Although the belt may appear to be
undamaged, some of the protective
properties may have been lost. Replace the
seat belt if it is worn or damaged.
make any modifications or repairs to the seat
belt. Contact an authorised Volvo
workshop.
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