There is a variant of DUERBECK s mark on a HOELLER dagger. For me a singn that at least several distributor marks have been applied "in house" as the EICKHORN variant of the DUERBECK mark also comes on bajonets (with nickled blade) and could not be applied after assembling.
Our late member Ford Crews did find out that these interesting, after 1938 marked daggers have tapered tangs (I never have taken this dagger apart) and have a very distinct handciseling on the crossguard.
Regards,
