Pressure regulator (make x female garden hose thread) reduces the pressure entering your system to the recommended operating pressure of your system. Male x female hose thread, 25 psi. Pressure is determined by your house pressure which is usually 40-60 psi. Drip or Soaker Hose systems are designed to work around 20-30 psi. If your pressure exceeds this psi, your fittings may blow off, be damaged or soaker hose may spray. If your pressure is to high, it may damage the regulator and water will seep out of the small hole. In turn it will need to be replaced. Know your pressure.
Tip: If you know you have high water pressure you might consider the #102 Heavy Duty Regulator, or the most heavy duty, #650 adjustable, with a gauge that works up to 160 psi. This is actually the same regulator they use in RV's for extreme pressure.
and you purchase the wrong regulator, it will cause it to malfunction and water will come out a little hole on the side of the regulator. The pressure regulator will no longer work if this happens. Know your pressure!