This compressor is able to reach pressures up to 60 PSI (4 mb), the maximum that can be shown by the LEGO analog gauge. It uses 2 NXT motors and 4 small compressors. With a gear systems reach the RPM required for this pressure. The user can select the desired pressure. With the pressure sensor from Mindsensor, the system stop when this pressure has been reached and start again when the pressure falls from this value.