Deane Goltermann Jan 22, 2014:

demonstration ... Since Rockfon sonar is a specific product by a well known provider of 'undertak', I tend to agree with Sven's idea.

Charlesp (asker) Jan 22, 2014:

good suggestion, but... It seems to be a simple ordinary installation.
I am going to presume (at this point) that it is some kind of error in the original, and that something else was meant here.

Sven Petersson Jan 22, 2014:

Could "Dem." = Demonstration A show installation?

Charlesp (asker) Jan 22, 2014:

for new construction I should mention.

Charlesp (asker) Jan 22, 2014:

Yea, it would be nice to have more context ... but I don't have any. So it might end of being a bit of a wild guess (as Sven mentioned).

sans22 (X) Jan 22, 2014:

Demontera undertak Rockfon Sonar? Just a guess