It’s easy enough to verify whether or not a product is certified. The more important question is, has the product been tested at the advertised flow rate by a third-party, ASSE-listed laboratory—and did it pass?
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How to Choose the Right Size Master Mixing Valve
Choosing a mixing valve too big for your needs will forfeit some level of low-flow performance, which can affect bather comfort and even safety. Our master mixing valve calculator lets you plug in your data so you get the right answer every time.