Another case of posting an example of a very run-of-the-mill stove solely for the purpose of trying to find out more about a small oddity. In this case what seems to me to be an oddity is the base provenance marking. All of the other Optimus No.1s and 5s of this vintage that I have come across are marked 'A/B OPTIMUS* STOCKHOLM* MADE IN SWEDEN' on the base. So what is the story behind this one being marked simply 'OPTIMUS*ORIGINAL'? The closest roughly comparable and contemporaneous use of the term 'original' I can find to this is in examples of 'Ursus' and 'Phenix' stoves uncovered by @gieorgijewski. Both of these appear to have been made for sale in Poland. Is that significant?