Ensure clean water supply with the Watts 0062094 1/2” 009-QT RP Backflow Preventer. This manual valve operates on water and is suitable for use in reduced pressure zone (RPZ) systems. Designed to prevent backflow, this unit is perfect for industrial and commercial applications. Made in the United States, this high-quality backflow preventer comes in a compact unit type and has a pipe size of 1/2 inch.