Expansion Tank

[Gren 24]

I have got a black expansion tank that I would like to fit on my 2004 tourer.It as got a piece on the bottom that I do not know what it is for. not got the same on the one on the tourer.Enclosed a photo,if some-one could explain what it is used for.any help would be much appreciated.

http://i925.photobucket.com/albums/ad100/Grena24/IMG_20140130_112749.jpg (http://s925.photobucket.com/user/Grena24/media/IMG_20140130_112749.jpg.html)

[T-Cut]

The photo shows the socket that was to take a coolant level sensor. Unfortunately, MGR didn't get any further than the socket.

TC

[Gren 24]

Thanks T-Cut,
It really had me wonderring what it was for.

Many thanks

Les