DIG's adjustable pressure regulators keep your drip system at the correct pressure for an efficient drip irrigation system. This female inlet - female pipe thread outlet regulator allows for adjusting the pressure of your system from 28 -60 PSI. The lower pressure offers protection to your drip emitters that otherwise could be damaged or not operate according to printed specifications due to excessive pressures. Use the pressure regulator on any irrigation system that needs a lower pressure. Install the pressure regulator after the filter in a drip irrigation system. Do not install the pressure regulator on a main line where the pressure regulator is under constant pressure. Adjusting pressure: To adjust the pressure, turn the off, remove the colored cap from the top of the pressure regulator and use a screwdriver to turn the screw under the cap counterclockwise to raise the pressure and clockwise to lower the pressure. Color: Blacks.