[DMXF]

According to the following UK supllier website the Karvel (or Carvel) had the heavy woven backing back in the day, which is not what original Cobra carpeting looked like:

"Originally, all BMC carpets were made from a carpet material known as "Carvel" which was a short pile carpet with heavy woven backing. This was superceded in the mid 1960's by what was then a "modern" carpet where the pile was flocked to a rubber composite backing and made by Dunlop. These materials are no longer available, so..."