RonA Active member Sep 7, 2021 #1 Friend has some of these, all new. 2 1/2" to 4" sizes. model 375ADA and others. I guess they are used to keep water in a building from back flowing into city water when city water is turned off or loses pressure .I can take pictures by request.
Friend has some of these, all new. 2 1/2" to 4" sizes. model 375ADA and others. I guess they are used to keep water in a building from back flowing into city water when city water is turned off or loses pressure .I can take pictures by request.
