The 6" Watts 773DCDA Double Check Detector Assembly was produced from 1998-1999. Similar internal parts to the 709DCDA, the 773DCDA was designed to be installed vertical. The body is a two cover, epoxy coated cast iron construction. The check assemblies are self contained bronze. The device has replacable bronze seats. The bypass was equipped with 3/4" 007M2 or 3/4" 007M3. No special tools are required for servicing.