This has had to be purchased well before the plumber comes to install it, as the locations of holes in the floor and wall have to be established. The plastic pipe in the wall is not a pipe for plumbing control commission purposes, but a vent duct. We have opted for an exhaust fan system called an “OdourVac” which exhausts from the toilet bowl by way of the overflow from the air space in the cistern. Take the pong from the source, rather than drawing it through the room! 28-12-05