Stern Defense AR-15 9MM Conversion Adapter - Compatible with S&W M&P/SIG 320 Magazines

$187.99

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Cheaper Offer Available

BattleHawk Armory lists a matched offer at $148.92, $39.07 (21%) less than this listing's $187.99.

Price Intelligence

Early read

Against lowest Matches lowest seen

Typical price Near typical ($187.99)

Data depth 2 days, 0 price changes

Only a few days tracked. Set an alert rather than trusting this yet.

The advertised price has held at $187.99 since tracking began on Oct 20, 2026; no price changes recorded.

7 retailers list STERN DEF. MAGAZINE ADAPTER - AD9 S M/SIG P320 9/40 MAGS; 7 in stock, in-stock prices run $148.92 to $187.99.