The PSI hole can accommodate a 2" diameter PSI gauge

established in 1982

com and we'll be happy to answer any questions you may have on filter softening products

4" diameter bottom cover plate

You may also want to buy a stainless steel bracket so this can be mounted to a wall

Pressure Reducing Valve (PRV) UPGRADE The PSI hole can accommodatePRESSURE REDUCING RO VALVE: PRODUCT SPECS Ideal for both residential and commercial applications, our Reverse Osmosis Pressure Reducing Valve is the perfect solution to maintain the integrity and functionality of your RO system. Invest in this essential component and experience the difference in your water purification process. Here are some of the benefits of choosing the RO pressure reducing valve: Premium Quality: The Reverse Osmosis Pressure