Hi, I recently purchased this "HIRSO" stove and while trying to date it, I found this 1923 price list showing the exact same stove—and the same trivet, too. Given that it does not appear in the 1921 list and was no longer in production by 1930, we can conclude that this stove was manufactured between 1922 and 1929. We can see how it is identical to its "sister," the Diamant.
