The 1" Ames 200B began production in 2003. Ames began to market the Watts 719 series as their model 200B. There are minor exterior differences between the Watts and Ames, but internal parts are the same. The 200B is a two cover, bronze body device. Covers thread into the body. Use caution when servicing as there is spring tension against the covers. Poppet design check assemblies with replaceable seats. No special tools are required for servicing.