Yes Dürkopp sold bicycles to millitary at this time and before also .
Catalog 1910 :
"Wir betonen aber noch besonders, dass wir die Fabrikanten der
Militär-Räder sind, welche seitens der Heeresverwaltungen vor Abnahme ganz besonders strengen Prüfungen unterzogen werden.
We would like to emphasize, however, that we are the manufacturers of military bicycles, which are subjected to particularly strict tests by the army administration before acceptance
But there is no picture from a military bike , a later Catalog shows a "Dienstrad " (police , judge etc.)
A lot of german brands sold to the military , most are grey (feldgrau)
But chainless was expensive , not used by military
Military have smaller chainring , but never chainless
Dürkopp military catalog picture from 1897
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