The force of an accident can cause a child to slide under a lap belt.
The device will not work with a lap belt alone.
Critics for several years have raised questions about the degree of safety provided by lap belts alone.
An estimated 150 million cars have only lap belts in the rear.
A lap belt and foot guard are also required equipment.
Riders face toward center of the boat and are usually secured by a lap belt.
Children 40 pounds and more should simply use the lap belt, the agency said.
To be completely effective, the air bag still requires the use of at least a lap belt.
Yes, that might work, he thought, taking off the lap belt and standing.
A lap belt is a strap that goes over the waist.