Oatey 041386 Cherne 8-Inch Single-Size Test-Ball Plugs, Small

If you are one of the multi-millions of sewer pipe plugging enthusiasts out there looking for an 8" pneumatic sewer plug to STOP THAT POOP!, look no further! This Cherne ("Cher-ney"?, "Churn"?) test ball (i.e. inflatable poop plug) will stop that sewage in its tracks! I use them to conduct septic and pump tank water-tightness testing, and to temporarily stop the inflow into septic pump tanks and wetwells when I'm performing pump flow tests. I remove the valve stem core, install about 10 feet of air hose on the valve, and add a pressure gauge and a new valve stem at the opposite end so I can inflate the plug from the top of the tank/wetwell. The gauge helps you ensure that you're not exceeding the maximum rated pressure, and also lets you monitor the setup for air leaks. Works like a dream! Just make sure you read the instructions on how to properly use these (be careful not to build up too much head on the upstream side...see manufacturer's limits), and for gods sake remember to remove it when you're done, or else the customer at the lowest elevation upstream will be ankle-deep in poo water!

Sorry but was totally disappointed kept deflating. Had to keep adding air every 7 minutes to keep it tight in the drain, did this for 2 1/2 hours. So I tried to just keep the air on ever so slightly then it popped. Your lucky cause I was definitely going to return but now I can not.

For plumbing pressure tests, I have no idea.I use these things to plug the exhaust pipes on my boat. The boat stays in the water all winter and the plugs keep the water out of the exhaust pipes. I install the plugs, air them up and then drain the exhaust system. The plugs are always about 1/2 way under water. They get some sun and constant brackish water on them. I got at least 10 years of service out of the first pair I bought and just bought a second pair in 2015.

Fit great, Inflated easy, sealed the pipe.