Chicago Pneumatic CPVS D 20 15kW 20HP Silent Screw Air Compressor - MADE IN ITALY. The Chicago Pneumatic Variable Speed compressor series CPVS allows you to drastically reduce your operating costs when your equipment is not working at full capacity all day long. Basically the inverter reduces the motor speed to match your air consumption and as a result, you save energy and money. The CPVS is great as a stand-alone machine or networked to a load-unload CP compressor where it can function as a master and regulate the air delivery for the whole site.