If you just got a notice or you're trying to figure out what device you have, start here.
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What to Do When You Get a Backflow Test Notice
A step-by-step guide to the annual notice from your water district: what it means, deadlines, and how to get compliant fast.
Read guideBackflow Preventers Explained
How backflow happens, how the main assembly types stop it, and why California requires annual testing.
Read guideRP vs. Double Check vs. PVB: Which One Do You Need?
Side-by-side comparison of the common assembly types, the hazards each is approved for, and installation rules.
Read guideMore quick answers are on our FAQ page.