EGR removal.

Just been reading comments about the removal of the egr, had a look at the td5 kit on ebay, £46 plus £18 for postage to Ireland. I have plenty of steel and drill and grinder, I reckon I can make the kit myself in an hour or so. Question is, what is the diameter or the pipe on the square flange? and I saw a picture somewhere with a rubber hose on the end of it going towards the grond, where does the hose go to? and what would happen if you went wading with the end of this hose open?

Thanks guys & gals.

What pipe?