Plumbing vent

[Jeff Eastman]

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[Joshua Hardesty]

That's a "no-hub" coupling, looks fine to me. There's a rubber band that the metal band you see compresses to create a seal. It's much easier to use one of those to splice something into a pipe than it is to use a regular PVC coupling. Say he wanted to add that cleanout. If the PVC couldn't be moved vertically, it would be very hard to get the PVC to fit inside the hubs on the tee. So, you can take a no-hub, put it on one of the pipes, then roll the rubber back on itself, slide it into place, roll the rubber back onto the other pipe, then clamp that metal band around it.