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Infant car seatBaby seatA booster seat or a
baby seat is a special chair for a baby that is placed on top of a normal chair. It helps them to be taller so that they can reach the table when then eat. For younger babies they have a special chair called a highchair that has a little table attached to the chair so that the baby can eat and cannot fall out of the chair.(
http://www.vocabulary.cl/Basic/Baby_Room.htm)
A
baby seat is rear-facing and can be fitted in the front or rear of a car.(BBC)
An
infant safety seat, also known as a child safety seat, a child restraint system, a restraint car seat, or ambiguously just as a car seat, is a restraint which is secured to the seat of an automobile equipped with safety harnesses to hold an infant or small stature people in the event of a crash.(Wikipedia)

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