AR-15 SD Mod 4 9mm Upper Receiver 4in M-LOK Complete - SD Mod 4 9mm Upper Receiver 4in M-LOK Complete Black
2 options
- 4", this page
- 16.1"out of stock
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Stern Defense
Overview
The Stern Defense SD Mod 4 9mm Upper Receiver is a complete assembly designed for the AR-9 platform, featuring a compact 4-inch barrel that makes it ideal for close-quarters applications. Its design allows for effective performance with 9mm ammunition, providing a reliable upper for builders focusing on maneuverability and control. This upper receiver is commonly found in pistol-caliber carbine builds, where versatility and rapid handling are key.
Specifications
AR-15 SD Mod 4 9mm Upper Receiver 4in M-LOK Complete - SD Mod 4 9mm Upper Receiver 4in M-LOK Complete Black
2 options
- 4", this page
- 16.1"out of stock
Available Merchants(1)
Prices checked
Stock Alert
Price and stock
The Stern Defense AR-15 SD Mod 4 9mm Upper Receiver 4in M-LOK Complete - SD Mod 4 9mm Upper Receiver 4in M-LOK Complete Black was out of stock everywhere we track for all of September 2026, and today the one retailer we track is out of stock. Listed prices start at $419.27 at Brownells for when it comes back.
Prices checked · refreshed daily across 37 retailers
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