The Watts 88004112 is a durable 1" backflow preventer with a double-check valve for maximum water protection in HVAC systems and other water applications. This backflow preventer, made of robust bronze, provides long-lasting performance and corrosion resistance, making it suitable for use in a variety of water supply systems. This is accomplished by its dual check valve system, which ... https://www.usapoolshop.com/88004112-watts-1-backflow-preventer-lf-w-double-check-valve