Toyota Prius Owner's Manual page 119

Pre-crash seat belts (front seats of vehicles with pre-crash safety
system)
If the system determines that a collision is unavoidable, the front seat
belts will retract before the collision. (P. 321)

Emergency locking retractor (ELR)
The retractor will lock the belt during a sudden stop or on impact. It may also
lock if you lean forward too quickly. A slow, easy motion will allow the belt to
extend so that you can move around fully.

Child seat belt usage
The seat belts of your vehicle were principally designed for persons of adult
size.

Use a child restraint system appropriate for the child, until the child
becomes large enough to properly wear the vehicle's seat belt. (P. 174)

When the child becomes large enough to properly wear the vehicle's
seat belt, follow the instructions on P. 117 regarding seat belt usage.

Replacing the belt after the pretensioner has been activated
If the vehicle is involved in multiple collisions, the pretensioner will activate
for the first collision, but will not activate for the second or subsequent colli-
sions.

Seat belt regulations
If seat belt regulations exist in the country where you reside, contact any
authorized Toyota dealer or repairer, or another duly qualified and equipped
professional for seat belt replacement or installation.
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1-4. Adjustable components (seats, mirrors, steering wheel)
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