See also:

How does the airbag supplemental restraint system work?
The airbag SRS is designed to activate when the vehicle sustains longitudinal deceleration sufficient to cause the sensors to close an electrical circuit that initiates airbag inflation. The ...

Airbag supplemental restraint system (SRS)
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Child booster seats
The belt-positioning booster (booster seat) is used to improve the fit of the vehicle safety belt. Children outgrow a typical child seat (e.g., convertible or toddler seat) when they weigh about 4 ...