The Keg King Purple pressure relief valve is suitable for maintaining 15 psi pressure in your fermentation for any pressure fermenter/Unitank series. It ensures the ideal pressure without the risk of exceeding the settings.

The purple PRV lifts when the pressure exceeds 15 psi and reseals at the end of fermentation, usually around 12 psi.

Note that during fermentation, a hissing noise may be observed when using this valve.