door unlock

Power door locks (also known as electric door locks or central locking) allow the driver or front passenger to
simultaneously lock or unlock all the doors of an automobile or truck, by pressing a button or flipping a switch.
Power door locks were introduced on the luxury Scripps-Booth in 1914, but were not common on luxury cars until Packard reintroduced them in 1956. Nearly every car model today offers this feature as at least optional equipment.
Early systems locked and unlocked only the car doors. Many cars today also feature systems which can unlock such things as the luggage compartment or fuel filler cap door. It is also common on modern cars for the locks to activate automatically when the car is put into gear or reaches a certain speed.

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