9 compressor models 4 cylinders, with displacement from 4.20 [30 Hz] to 57.30 [87 Hz] and nominal power from 1.5 to 7.5 hp. The inverter is mounted on the compressor and is pre-programmed to be managed by an external OID controller or a pressure transducer that can be mounted on the suction line. The calibration of all the parameters that control the inverter can be customized according to the specific application.