Protect your boat water system appliances and pump from damaging pressures of unregulated marina water hookups with the PAR Regulator. It reduces high water pressures (up to 100 PSI down to 35 PSI). It features a built-in backflow preventer. Easy to install and features an easy-to-clean in-line filter. A compact permanently installed flush mount unit with brass garden hose fitting that simply connects between your dockside water entry and garden hose water hookup, Port is 1/2" MPT. Chrome plated housing.