The Caleffi 15mm Pressure Reducing Valve 533841H is a single union pressure reducing valve made of brass, designed for use in water systems. With a downstream pressure setting range of 1-5.5 bar and a maximum upstream pressure of 16 bar, this valve is suitable for a range of applications. The outlet diameter is 15mm, and the valve features a compression connection for easy installation. The valve is adjustable, with a minimum adjustable output pressure of 1 bar and a maximum output pressure of 5.5 bar, making it versatile for various pressure needs. Designed by the reputable brand Caleffi, this pressure reducing valve is reliable and efficient for maintaining optimal water pressure.