Help me identify this periscope

[Control88]

I found this periscope from basement and I have no clue is this ww2 or modern-day stuff.
I did quick google search and it looked like ww2 german trench periscope, but i am not sure.

[Waleed Y. Majeed]

It looks old and could very well be German with that “dow” code. Not made in Germany though, if it is ww2 and the letters are the ordnance codes as I think.
Have a look at this list:
https://oldmilitarymarkings.com/codes_f ... a_c-e.html

Waleed

[Natter]

dow = Opticotechna GmbH (zielfernrohre, entfernumgsmesser) in Prerov, Chech Republik.

[Xavier]

google trench periscope dow, its that.