Hi Forum
I have just got this ammo with nice stamps, I am doubt about it, I do not know much about German Anno, but I fund a link that perhaps describes this one:

400 521 1943 2cm Kpf.Z.Zerl.Fg.bzz

TYPE NOMENCLATURE MADE OF DELAY PROJECTILES NOTES
NDF/LAA Kpf.Z.Zerl.Fg. Steel None 20mm Incendiary German Navy uses

Length about 9 cm

Diameter about 16 mm, 98 Gr

http://www.navweaps.com/index_nathan/German_WWII_Fuzes.pdf
Regards
John

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