RRA Improved CAR Buttstock Lock Ring Nut?

[minutemen1776]

I was perusing the Rock River Arms website earlier and found something I was unfamiliar with. Right on top of the listing for lower receiver parts, there was an entry for an "Improved CAR Buttstock Lock Ring Nut" priced at $6. Unfortunately, I found no info explaining the purported improvement. Does anyone have one of these or know what makes it special? Thanks.

 

[minutemen1776]

No one has a clue on this one? Maybe I'll have to ask RRA.

 

[minutemen1776]

Still nothing. I guess the "improvement" wasn't well advertised. I sent an e-mail to RRA, so maybe I'll hear from them soon. I'm not sure why I'm so curious about this.