Hey. I noticed on the back left end of my mobius, there is a hole with a cap on it that says atwood. I know it has to be for some kind of pump but not sure what it is. Its not the ballast, thats a little further up on the boat, and its not the bilge, thats on the other side towards the front. I can reach my hand back behind the rear wall and feel a tube running into it. I was just wondering if anybody could tell me what this is. thanks.

pic can be seen at http://forums.wakeboarder.com/viewto...?p=56602#56602