A very nice piece I picked up recently and I thought you might be interested in it. A Lange & Söhne Glashütte, "beobachtungsuhr" Cal 48.
Ordered by the German Navy in 1937, their requirements couldn´t be met though, untill autumn 1940, which was the start of production.

As Lange was not able to supply the ordered amount of watches in time, they were forced to outsource the finishing to their watches to these four Watchmakers/Companies;

• Andreas Huber, München-Berlin
• Alpina-Dugena, Berlin;
• Conrad Felsing, Berlin;
• Wempe, Hamburg.

I have seen all of these watches except the one from Felsing. Now I´m the proud owner of one of them!
The company that had assembled and finished these watches were endorsed on the front of the dustcover. Mine clearly marked Conrad Felsing, Berlin.

There has been so much written on these watches, that I will spare you my version and give you a link with a translator, where all can be read: Link

Here the engravings;
on the dustcover there is a light engravement in a rectangle.
Top line says Werk.(movement) A.Lange & Söhne
2. line, Nr 204346
Then there is a dividing line and underneath it says;
Fertiggestellt ( Completed, finished)
Conrad Felsing
Berlin

On the Caseback there is the swastica and eagle, in the middle is the Watch Nr. 204346, on the bottom is a Marine Nr. M 17??7.

The caseback has been heavily polished to remove the military markings, but under a certain angle most can still be read.
It is a great pity that it underwent this treatment and I don´t even think it was removed by requirement, but simply to use an otherwise perfectly good, militarily marked watch, which no one was proud of in the early post-war years.
Enjoy the pictures,
Regards
Jimmy

Dial

Dustcover

Movement

Caseback


Inside caseback