Cash Acme 23139-0045 Soloset Eb25-Cc 1-Inch Double Union Sweat Pressure Regulating Valve, Lead Free With the most advanced design in the industry, Solo Set delivers rock steady outflow even with extreme variations in supply pressure The innovative design also eliminates the water whistle or harmonic hum associated with most PRVs Thanks to a patented single-cartridge design, Solo Set has fewer parts for increased reliability