Doesn't work unless you have a car with a mainstay mechanism in the automatic door locks. The solonoids in the door have to be magnesium carbonate, which most cars aren't...unless you drive a Saab, also, most late model cars newer than 2000 have an L-Link forged dual piston compression ring, making it near impossible for it to be opened by air pressure alone. There are actuators connected to the latch and the body controller supplies power to the door-lock actuator for a timed interval. Meaning, air pressure isn't going to do shit.