Still screwing in a test ball and wondering if the test will hold?
GT Water Products (www.gtwaterproducts.com) has had a larger verions of the popular TTMP plug for a while now but wasn't content to stop with what they had. Last year they introduced the TTMP-6WF, a 6" mechanical test-tee plug with a built-in water supply, and now they have done the same with the 4" TTMP.
Introducing the TTMP-4WF. Holds 70 feet (35 psig) of head pressure, fits all materials (cast iron, PVC, DWV).
How does the TTMP work? Check out this video >>
Read more about the TTMP-WF here >>