Fortunately, the numbering 853/16 allows this Ikoflex to be identified. Indeed, in 1938, Zeiss Ikon released a new version numbered 852/16 of its Ikoflex II, and gave it the name Ikoflex III. But,certainly annoyed to have been left behind by Rollei and his Automat of 1937, Zeiss released in 1939 another Ikoflex, the 853/16, even more sophisticated.

Zeiss could have called it Ikoflex IV ... well no! Presumably because of some marketing mystery, the 853/16 is called Ikoflex III, and the previous "III" is demoted to "II / III" to distinguish it from the previous "II". Simplicity did not seem to be in order at the time.

Extract from the "retro" section of P.H. PONT in "Chasseurs d’Images" from January-February 1999:
"The people at Zeiss have many other ambitions in mind: they want to exceed the Rolleiflex.Automat of 1937 by a hundred cubits! Which will give us the extraordinary Ikoflex III ...
On the “III”, everything is excessive. The shutter, a Compur Rapid at 1 / 400th, of large diameter, compulsory to house the lens. The lens? A huge Tessar 2.8, unparalleled in the Rollei range. All this weighing very heavily, Zeiss did not hesitate to cast a magnesium case, which brings the weight of the set down to 965 grams - which is exactly that of the Automat 3.5. The advance of the film and the (coupled) cocking of the shutter are handled by a crank. And the sports "iconometer" viewer has been replaced by a van Albada-type collimated optical viewer, which corrects parallax! For once, Rollei is really behind.
The addition now: the Ikoflex III is sold 50% more than the Automat. This is one of the reasons why this fabulous device, the last Zeiss marvel of the late 1930s, will also be the one with the shortest career: launched in 1939, it was discontinued the following year. "

When it was launched, the 853/16 was described in advertisements and catalogs as the "New Ikoflex III" or "the Ikoflex Automatic". It is the most advanced and the last of the pre-war Ikoflex.