Pressure Regulation: The 3 Pcs 6.5 8 9 Bar OPV Springs Set is designed as an alternative to the factory-set over-pressure valve (OVP) of the for Gaggia Classic espresso machines. Optimal Extraction: The factory-set pressure of 15 bar in the for Gaggia Classic OVP might be too high for using a classic espresso portafilter basket.
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