Zamak object.

[Stuka]

Hello,

I found this thing last year, but I can't figure out what it might have been. I hope someone will recognize it.
It is made of zamak. No markings whatsoever.
The thread matches the thread of a No.117/No.119/...
Length: 3 3/8" - 8,5cm
Diameter:2 5/8" - 6,7cm











Thanks in advance,

Thomas.