The Watts 994 Series Reduced Pressure Zone Assemblies are a stainless steel body device. Check valves are self contained, cam style. Single victaulic cover design, both checks are accessed from the top. Relief valve hangs from the bottom and unthreads from the body for ease of service. Module style relief valve. Light weight and compact design. No special tools are required for servicing, but a cam check removal tool is available for easy of maintenance.