What is this stopper tool for plugging a pipe?

[LikeABigFriedEgg]

I was watching a youtube video wherein a guy inserted a tool in a copper pipe to stop water coming out.

It looked like a cylindrical rubber stopper on the end of a rod. He stuck it in and tightened it, seeming to squeeze the plug from top to bottom, causing the plug to squeeze outward against the walls of the pipe, stopping the water.

Then he put the rod through an open ball valve and sweated the valve onto the pipe.

What is that tool called?

 

[voletl]

test tite twist n seal.

Jet swet.

Google them find out which one is better for you they all go by different names

 

[LikeABigFriedEgg]

test tite twist n seal.

Jet swet.

Google them find out which one is better for you they all go by different names

Thank you, voletl. The one I saw and described was Jet Swet. Kind of costly, aren't they.

 

[voletl]

Yeah jet swet is, look up the other brand. You can find a good deal if you look

 

[SolagPlumber]

Jet sweat.