The 475DA-475DAV Reduced Pressure Detector Backflow Assembly is utilized in high hazard, fire protection applications to protect against both backsiphonage and backpressure. The 475DA is shaped in the n-Pattern for new or retrofit installations in compact spaces, while the 475DAV is shaped in the z-Pattern and installed vertically in a flow up orientation. Both models include a small footprint for quick and easy fire protection retrofit applications, as well as a metered bypass system to detect leaks and any unauthorized water use, saving you valuable time and money on repairs and maintenance costs.