The A4A outlet family of regulators are compact, heavy duty, pilot operated, and have remarkable functionality. The regulator will gradually close when downstream pressure begins to rise above the setting and will gradually open when pressure begins to fall below the setting. The regulator cannot maintain set-for pressure if uncontrolled branch pipe lines feed into the main pipeline downstream of the regulator. The valve's purpose is to modulate flow of refrigerant gas or liquid to maintain constant downstream pressure as set-for, despite load fluctuations.