Looks like an Ace stock, and it's definitely a folder.
Ace stock, started as a 8.5 incher, but I chopped it by an inch (didn't wanna deal with shipping it back)
The 7.5 ace stock with folding block and internal block brings it down to warsaw length, get the 8.5 for nato length..
You do have to cutt off your rear tang though. But once you cut you'll never wanna go back...
FSB is from blackthorn, they have like...millions of them! All at a nice price of 25 bucks. Note that it doesn't include any of the farkles of a normal FSB--no plunger, no spring, and no sight post o