Atmospheric backflow prevention in an economical valve. With the PGV-ASV, irrigation systems that require back-flow prevention for every zone can enjoy simple operation and trouble-free performance without the need to install a separate back-flow preventer. This convenient all-in-one unit offers a host of features that professionals expect from a Hunter valve, a rugged diaphragm that provides a leak-proof seal, internal bleed for manual operation, stainless steel hardware and springs, stainless steel bonnet screws, and heavy-duty PVC construction that is both corrosion- and UV-resistant. The valve also includes flow control, allowing precise adjustment of the flow plus manual shutoff. For proven reliability in an anti-siphon/electric valve, depend on the PGV-ASV.