I see there are standard and heavy duty QD swivels available. Which is OE on the M&P 15-22 MOE [818034]? The width of the loop is one variation -- 1" vs 1 1/4". But are the mounting pins different?

I believe the stock has the push button swivel.
For a picatinny rail QD or Push Button swivel, go here;
Slings and Sling Accessories : Tacticool22, Tactical .22 Rifle Parts and Accessories
I can't stand that huge sling loop on the standard stocks.

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