G'day @Torgeir D Teigum and welcome. They run on Bensin but better to run on Renset bensin or Heptan (if I got this part wrong please someone correct me) Have a look at this post. https://classiccampstoves.com/threads/primus-1205-c-1938.33984/ A set of instructions here - https://classiccampstoves.com/threads/primus-1205-1938.33975/