The N-H420 two-stage regulator is an LPG liquid withdrawal high pressure regulator with a heat exchanger that will vaporize enough fuel for up to 350 HP engines.  With the N-H420's improved vaporization characteristics, liquid propane enters the regulator and then is vaporized using heat from the engine's coolant. Tank pressure is reduced to approximately 1.5 psi. As negative pressure is transmitted from the carburetor to the regulator, the regulator releases propane vapor to the carburetor. This regulator is equipped with a silicone secondary diaphragm.