Shop propane regulators from trusted brands like Emerson Fisher, Fairview Fittings, and Marshall Excelsior. Propane regulators are commonly installed at the outlet of a propane storage container to reduce the PSI of the gas into a desired flow rate.  First stage propane regulators are best used in situations where inlet pressure is constant, and second stage regulators are best in applications where more variables exist in the system. Both types of regulators have high-pressure ratings and have uses in both industrial and residential applications.