The ZB mags were probably imported by Global Trades - Armory USA years ago. The owner supposedly had a warehouse full of guns, parts, ammo, etc. Some of it started showing up at local gun shows earlier this year after he passed away. That’s where I bought one; mistakenly thinking it was a Mk1 .303 Bren mag. There was also a new in the box milled receiver from Arsenal, Sofia, Bulgaria, serial number “X 5”, a box of new SLR-100H receivers and lots of Bulgarian AK parts. Apparently Mr. Yates imported quite a bit from Bulgaria.
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