QE QUALITY oil separators feature: stainless steel needle & ball, hermetic welded construction with steel oil return system (1/4″ or 3/8″ SAE connection), dependable shut off system (float operated valve), solid copper connection, anti-corrosive epoxy powder paint finish, and maximum operating pressure: 3.5 Mpa / 500 PSIG (compatible with R-410A refrigerant).