ARKSEN Air Operated Vacuum Pump R134A R22 R12 AC Refrigerant Refrigerant Charging 4.2CFM Pneumatic Auto Suitable for Automotive Air Conditioning System, Home Air Conditioner, Refrigerators, Freezers and Other adding/Charging Refrigerant Duty! Vacuum Capacity: 28.3 Inches Of Mercury At Sea Level @ 90 PSI Air Inlet: 1/4"- 1/8NPT; Connect the Air Line and it offers Full Vacuum within minutes Vacuum Capacity: 28.3" Of Mercury At Sea Level @ 90 PSI; Vacuum Port: 1/2 Inches Acme (R134a) & R12 Connector Air Pressure Range: 75 -180 PSI - Air Consumption: 4.2 CFM @ 90 PSI