Word forms: (regular plural) passive restraints
noun (Automotive engineering: Vehicle components, Bodywork, controls, and accessories) A passive restraint is any device, such as an air bag, that operates automatically to prevent you being thrown out of the seat of a vehicle if there is a crash. ⇒ Passive restraints such as air bags or automatic seat belts are required in all vehicles. ⇒ The passive restraint rule required auto makers to install either air bags or automatically fastening seat belts. ⇒ Air bags are significantly more expensive than other passive restraint devices.
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