The Wilkins 475DA and 475DAV are reduced pressure detector assemblies (RPDA). They are available in 2 1/2″-10″ sizes and have been in production since 1998. Their bodies are made of epoxy coated ductile iron. The 475DA and 475DAV utilize a 3/4″ 975XLD for the bypass assembly. The 475DA is setup for an “N” pattern installation and the 475DAV is setup for a vertical “Z” pattern installation.