This application allows for sizing and making calculations for pipes and conduits carrying water or air, respectively for hydraulic or aeraulic plants.

This Watts LF009M3QT-3/4", 0391003 Lead Free Reduced Pressure Zone Backflow Preventer is designed to prevent the backflow of polluted water from entering into the potable water supply due to backsiphonage and or backpressure in accordance with national plumbing codes and water authority requirements. Its compact modular design facilitates easy maintenance with a single access cover for in-line repairs. It is ideal for protection in continuous pressure piping applications and at cross-connections identified as health hazards and for contaminants at the service line entrance. This assembly consists of a lead free bronze body, 3/4 inch NPT end connections, quarter turn ball valve shutoffs with tee handles, top mounted test cocks, two in-line independent check valves, captured springs, and replaceable check seats with an internal relief valve for reduced space requirements.