Double Check Valve Assembly

This four inch lead free double check valve backflow preventer assembly is designed to prevent the reverse flow of water of non-potable quality from being pumped or siphoned into the potable water supply due to backsiphonage and or backpressure in accordance with national plumbing codes and water authority requirements. site

Ideal for protection at cross-connections identified as non-health hazards and from other contaminants found at the service line entrance. This compact modular design with a single access sleeve for easy maintenance is approved for horizontal or vertical installation in accordance with the direction of the flow arrow on the assembly. It consists of a stainless steel body, tri-link check valves, outside stem and yoke resilient seated gate valves, and test cocks.

Only after posting the Thursday photo in the March 12th Photos collection did I notice the tag with a QR code. I returned Friday to scan the code and learn that this mechanism had more to do with fire hydrants than irrigation as previously assumed. Or did it?