The Strike Industries AR stock stop is being advertised as a "compliance part".
I know NJ requires "feature" rifles to not have an adjustable stock, but the state law does not give much detail about that. People ASSUME it means using roll pins or otherwise (semi) permanently affixing the stock. However, the law does not state that, just that it cannot be adjustable (I don't know if it mentions "removable", nor do I know how they would class that as ALL stocks are removable with the right means). Magpul FCS stocks are easily removable/swappable, yet most consider that sufficient because it does not "adjust". So why not a Strike Industries "AR stock stop" (which stops adjustment without being permanent)?

What are your thoughts on this for use in NJ? Thanks for any feedback!

Product:
http://www.thefirearmblog.com/blog/2017/07/05/new-strike-industries-ar-stock-stop-compliance-part/

If I had to take a guess, I'd say since it is non-permanent and easily removed, they would say it's not allowed.

While I agree that general consensus would agree with you, I'm not sure where people get this "permanent" notion from?
Unlike permanently attached muzzle devices (often used to bring legal length to 16"), I don't see any legal guidance for any legal means of "permanent" for a stock.
All I can find on it is this:

(per NJ DOJ site) "semi-automatic rifle that has the ability to accept a detachable magazine and has at least 2 of the following:

1) a folding or telescoping stock;
2) a pistol grip that protrudes conspicuously beneath the action of the weapon;
3) a bayonet mount;
4) a flash suppressor or threaded barrel designed to accommodate a flash suppressor; and
5) a grenade launcher; "

Are there any links to any info regarding whether the non collapsible stock has to be "permanent" or not? I'm looking at it from the standpoint, "so long as it does not "collapse" , AT THE MOMENT (whether temporarily or permanently), it should be GTG per NJ DOJ. But.. of course no one wants to be the one to test the legal standings (and I'm sure that's why people go way overboard with it).
Again, I'm just not sure.
Can anyone please provide any links to any legal definitions or methods for this?

Nope - because there are none.  The "general" assumption here is that a stock is collapsible, or telescoping, if it's length can be changed without the use of tools.  There is no legal interpretation stating that that's what the statute means - because even the part about collapsing or telescoping stocks isn't in the statutes.  Rather, it's from a 20+ year old interpretation of the phrase "substantially identical" issued to all state prosecutors by the then-Attorney General.

Dang, good to know! Thanks for the info!

Ugh... so yet it's more of the "can't have that" without defining what "that" is, kind of deal. Yikes... I'm glad I moved out of NJ (grew up there). Unfortunately, I still do some shooting there (have some family there), so I'm trying to stay within the law without seriously modifying my rifles (it's bad enough that I have to pin a few comps on a select few AR's I bring there).
I guess I'll just have to designate a few of them as "NJ" AR's and leave 'em that way.

Hmm what if you used it in conjunction with epoxy?