Alright, so here's our trap. Here's the stop point on the inside of a trap on the hub where the pipe's going to bottom out of it. So what I want to do, so you can see it's the same on the extension tail piece. So I want to stick this up there as high as I can get it. Bring this over and get my mark. That looks about right. So we're going to take this like so. A voila. Now that I've got my measurement for my extension tail piece to bottom out, to the bottom of the trap, you'll notice that this arm. They gave us a gesture to push it as far back as you need. To make sure that the drain from the laboratory is going to line up with the drain coming out of the wall. So we're going to go ahead and slide it back in and take my trap. And we're going to line it up right on it. So we're going to go ahead and snug the nut up by hand. Okay.