Peter,
It was from this company;
http://www.noisestopsystems.com/
This is the one I bought;
http://www.noisestopsystems.com/buy_...roducts_id/134
It works really good and stops the chassis ringing like a bell. Also, it doesn't seem to soak up water so the car will dry out quickly.
Driving up the road, you can't hear any noise coming through the chassis.
I bought 6 meters (it's 1 meter wide) and stuck it down with a about 2 litres of 3M glue (there is a self adhesive option as well). I've covered the whole of the interior especially around the bulkhead. The marlin carpet glued on top of that making the car really quiet and giving it a quality feel.