The PISTON-type pressure reducing valve PN 25 is an automatic valve that reduces and stabilizes the pressure of a fluid in a water distribution conduit according to a preset value. The use of this hydraulic device is necessary if the maximum possible pressure at any point in the water distribution system can reach or exceed the relative maximum allowable working pressure, or if the installation is equipped with devices that can be operated exclusively at pressure levels lower than the one available in the system. The piston-type pressure reducing valve is designed for use in either internal or external water distribution systems, where the water main pressure values do not surpass 25 bar. The thermoplastic material of the internal piston structure guarantees rigidity, strength and an enhanced regulation precision thanks to the compensated seat. The O-rings, in antistick-slip Perox EPDM elastomer with a low coefficient of friction, are durable and require only limited maintenance interventions. The internal finish of the body and the broader dimensions of the passage allow high performances even with a minimal water draw. The piston-type pressure reducing valve (PN 25) is used in air conditioning plants, sanitary installations for water supply, irrigation systems, compressed air (not oil mist) distribution systems, fire suppression piping (it should be borne in mind that local government standards for fire protection must always be observed), and sanitary installations for water supply in buildings (according to EN 806-2 and EN 805). This product adheres to the standards set forth by the European health authorities for the transport of alimentary fluids and potable water.