it came like this...it's the 13 RD from my Hellcat OSP...I've never used it, just had it in my range bag w/ the 11 RD...I didn't wanna damage it. I guess I'll leave it alone...
It‘s supposed to look like that, that tab keeps the mag from sliding off the base pad.
to disassemble the mag push a punch in the hole at the bottom of the base pad. Your tab will push up and will clear the base pad allowing you to take apart.