The Stern Defense Mag-AD9 9mm/40 S&W Glock Magazine Adapter transforms a standard mil-spec AR-15, M4, or M16 lower into a pistol-caliber platform that accepts Glock 9mm and .40 S&W magazines. Machined from aircraft grade aluminum with a Type 3 hard anodized finish, this compact adapter installs in seconds and integrates a reliable last-round bolt hold open for smoother operation and easier reloads.

This adapter is ideal for shooters who want to train with cheaper pistol ammunition while retaining their familiar AR-15 lower, or who prefer a dedicated pistol-caliber carbine for range use and practical shooting. Its design works specifically with 5.56mm lowers and requires a Glock-cut bolt and appropriate buffer setup, providing a clean, dependable interface between your AR and Glock magazines. Stern Defense is known for thoughtful engineering and precise machining in their AR accessories.

Key Features:

• Manufacturer: Stern Defense
• Model: Mag-AD9 Glock 9mm/40 S&W Adapter
• Caliber: 9mm / .40 S&W
• Condition: New
• Action: Not Applicable
• Finish Color: Black Type 3 Hard Anodized
• Unique Features: Converts mil-spec AR-15 lowers to accept Glock 9mm/.40 S&W magazines, last-round bolt hold open, installs in seconds, requires Glock-cut bolt and proper buffer
• What's In The Box: Mag-AD9 Glock magazine adapter
• Length: 6.8 Inches
• Width: 4.4 Inches
• Height: 3.4 Inches