The 2" Watts 007M1 DCDA double check detector assembly began production in 1995 and is still in production. Equipped with a bypass meter, the 007M1 DCDA is commonly found on fire supression systems. Several different bypass assemblies have been used. Many common bypass assemblies use 3/4" 007M1, 3/4" 007M2, or 1/2" 007. The main device uses a bronze body equipped with epoxy coated, threaded, OS&Y gate valves.