Looks Mini-14-ish. Too bad it can't be installed on any lower receiver. If you go to Ares's website and download the brochure, you can see that end of the receiver where the stock installs is different...it's wider. I'd retrofit (if retrofit was possible) mine if it came between keeping it and losing it. But with current laws in California, it wouldn't matter if the butt stock was fixed or not. It's the semi-automatic fire with the quick magazine changing, capability that the [uneducated] politicians freak out about. Overall length is a federal requirement. Maybe this will fit the bill for the NY laws. It looks a heck of a lot better than the Rube Goldberg stocks that have been coming out to get around those laws.
Anyway, if they can make it work on a current lower, then they'd have a really amazing product. Maybe they'll see this post and design the MOD II version for retrofit on standard AR lower receivers.