So I now have in my possession two different sets of Poul Volther chairs, and some are about 3/4" taller than the others. Did he change his base model at some point in his production? The taller ones have the Danish furniture sticker, the shorter ones don't, so at first I wondered if they were fakes, but who would bother to fake this chair? And closer inspection the shorter chairs have faint red stamps that say FREM R... Does anyone know about the history of his productions? 
Actually its not that...
Actually its not that uncommon to see the same chairs in different heights. Another example is Wegners Y-chair which also comes in two different heights. When exactly it happened i do not know, but at some point it was decided to add 2cm to the height. Dunno if it was because people was getting taller or they just found out it was better ergonomically. The standard height for a dining table has changed as well from around 72cm in the fifties to 74-75cm now.
So my guess is your taller set of chairs is probably just from a later production.
The stamp is from "Frem Røjle" who did indeed produce a few of Poul M Volthers furniture.
Hope that was of some help
-Manp
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