The 3/4" Watts 919 Series Reduced Pressure Zone Assemblies began production in 2003 and are still currently being produced. The 919 is a bronze bodied device with three covers. Check valves are poppet style and the relief valve is a stem type. Springs are not contained and covers will have tension, use caution when servicing. In 2010, the LF919 was introduced to comply with the new "Lead Free" laws. All repair parts were converted to lead free in 2013. Lead free repair parts will fit both regular 919 and lead free LF919 models. All 919 models have replaceable seats and require no special tools for repair.