Fully automatic operation for fast recovery of Class III, IV and V refrigerants including R-410A, backed by the best warranty in the industry. The CPR (Constant Pressure Regulator) valve automatically reduces the pressure of the refrigerant being recovered - regardless of which refrigerant - without slugging the compressor. Turn the single control valve to ''liquid'' or ''vapor'' settings, and the machine will complete recovery while you work on other aspects of the job.