A pressure regulator is necessary if you are allowing campground water pressure in your plumbing system. It protects your white hose and all the plumbing in your vintage trailer against damaging unregulated water pressure found in far too many campgrounds.
This effective and simple regulator is conveniently screwed on to your white drinking water "garden hose" at the female end where you hook your hose to the campground supply. Regardless of incoming pressure, it regulates incoming water pressure to a safe 40-50 psi.
Unlike some other regulators available, this one conforms to CA & VT lead laws for drinking water fixtures.