Stern Defense built the Mag-AD9 to convert a standard mil-spec AR-15, M4, or M16 lower to run Glock-pattern 9mm and .40 S&W magazines, installing in seconds without gunsmithing. It’s machined from black aircraft-grade aluminum and adds a last-round hold-open feature the AR platform doesn’t normally have in this configuration.

Key Specifications

• Converts an AR-15/M4/M16 lower to accept Glock-pattern magazines.
• Compatible with 9mm and .40 S&W Glock magazines.
• Installs in seconds without gunsmithing.
• Adds a last-round hold-open feature.
• Machined from black aircraft-grade aluminum.
• Measures approximately 6.8 inches.
• Manufactured by Stern Defense.

Frequently Asked Questions

Does this replace my AR-15 magazine well entirely? It adapts the lower to accept Glock-pattern magazines in place of standard AR magazines, rather than modifying the receiver itself.

Does it work with both 9mm and .40 S&W Glock magazines? Yes, Stern Defense lists the Mag-AD9 as compatible with both calibers.

Buy the Stern Defense Mag-AD9 Glock Magazine Adapter

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