An additional input with a nipple is mounted in the receiver. The car owner periodically pumps the air suspension system with a usual compressor, raising the car to the desired level. So he drives like on a springs in one position, most often in the second position. If the system is unpressurized, during some time the air will go out, then car lowers to the first position, and the driver again must pump air into the pneumatic system with any compressor capable of providing at least 8 atmospheres pressure in the system.