20mm mk-2 cartridge marked A.G

I have a 20mm mk-2 cartridge marked A.G.-1942 that I am unable to identify. Any help regarding its origin (country and manufacturer) would be appreciated. Thank you.

Hi, it was made by Aluminum Goods Mfg. Co. of Manitowoc, Wisconsin.

Regards,

Fede

Thank you so much for your help and fast response.

Tony Garcia

Tony, you are welcome. Please, can you post pictures of the complete cartridge and headstamp?