[StufflerMike]

There‘s a Laco Forum on WUS (jusr saying).

One of my former posts:

The Laco Sport history is a story of success. Laco Sport models, almost uncountable, were very famous in the 1950s to 1960s.

The years up until 1959 may be regarded as Lacher's "golden age". Laco enjoyed a strong market position with the manual wind and - starting in 1952 - with the automatic models, while Durowe supplied various watchmakers with an ever-increasing number of reliable and high-quality movements.

Seen through the eyes of collectors and enthusiasts of German precision engineering, this period offers a wealth of particularly interesting models. The "Laco-Sport" was the first one and introduced the "Duromat" - 11 ½ lines (552 cal.), the first automatic movement to be produced by Durowe as of 1952. This movement, with its 18,000 semioscillations and two-directional rotor, based on the 422 cal. manual wind, made Durowe one of the first German manufacturers of automatics.

Laco's history: The Laco (Lacher) History

You‘ll find more Laco Sport watches on the Laco Forum, here‘s just one link

What year is this Laco Sport

 

[StufflerMike]

So is this watch early 1940s or 1950s?

Late 1940s/early 1950s. Earlier models (1930s to 1940s) had a different case as you can see in the catalogue pics I added (special thanks to Uhrforum member MaJoLa). Another Sport with case no. 7344 was dated 1940s.

A lot of „early“ Laco Sport models were fitted with a Laco 526 (basically a Durowe 410). Production of the movement started in 1935.
In the late 1950s Laco Sport models were gifted for VW owners for 100.000km. Those of the mid 1950s had a Durowe 422 with inhouse shock protection -„ Duro-Swing-Stoßsicherung“.

 

[StufflerMike]

Thank's. I didn't know about the Laco Forum.

My standard advise is to familiarize with WatchUSeek and its fora prior to posting.