A very rare indeed survivor of the early age of photography made, I believe, for around 3 years circa 1920-23 and yet another example of Dutch-German ingenuity, being the very first incarnation of a single lens reflex and certainly the first for sale commercially SLR EVER on the market (which is what makes it such an important camera). Essentially this is a very simple fixed focus, two speed "box" camera the 1st speed is unknown to me but works as should and also "T" setting. The f stops 6:8, 12:5 and 25 are operated by a simple pull up slide and with a waist level view ground glass view finder operating through the lens just as any SLR.
The lens is Ihagee Anastigmat TRIOPLAN 6:8 f=8cm. The film is loaded into a removable wooden spool holder complete with a wooden and metal wind on spool. I can't say I've ever seen another for sale in UK. It's in pretty good condition all around considering it's great age and remarkably everything still works but do bear in mind it was made almost 100 years ago so if you do decide to try and actually use it - don't expect modern standards of photography. This camera really is a wonderful item of photographic history and for the serious photographic researcher to use the camera (all I've ever done is display it) perhaps before consignment to a museum for display , would be interesting.
A once in a life-time opportunity for the genuine informed collector/museum to acquire this very rare camera serial number 40837. One watcher has told me that it is most likely to date from 1922 according to serial number...The item "IHAGEE ROLL-PAF 21 REFLEX 120 roll film SLR Box camera Circa 1921 VERY RARE" is in sale since Friday, February 21, 2020. This item is in the category "Cameras & Photography\Vintage Photography\Vintage Cameras\Box Cameras". The seller is "michaelavron1" and is located in Bournemouth. This item can be shipped worldwide.