Buy Car Booster Seat

booster seat
An extra seat or cushion placed on an existing seat for a small child to sit on
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.
(Booster Seats) Booster seats are not permitted in any Spaceships vehicle.
(Booster Seats) Are intended to be used as a transition to lap and shoulder belts by older children who have outgrown convertible seats (over 40 pounds). They are available in high backs, for use in vehicles with low seat backs or no head restraints, and no-back; booster bases only.

buy
obtain by purchase; acquire by means of a financial transaction; "The family purchased a new car"; "The conglomerate acquired a new company"; "She buys for the big department store"
Obtain in exchange for payment
bribe: make illegal payments to in exchange for favors or influence; "This judge can be bought"
Pay someone to give up an ownership, interest, or share
Procure the loyalty and support of (someone) by bribery
bargain: an advantageous purchase; "she got a bargain at the auction"; "the stock was a real buy at that price"

car
A road vehicle, typically with four wheels, powered by an internal combustion engine and able to carry a small number of people
the compartment that is suspended from an airship and that carries personnel and the cargo and the power plant
a motor vehicle with four wheels; usually propelled by an internal combustion engine; "he needs a car to get to work"
A railroad car of a specified kind
a wheeled vehicle adapted to the rails of railroad; "three cars had jumped the rails"
A vehicle that runs on rails, esp. a railroad car