AR-15 M4 Build KIT M-LOK 5.56mm - AR15 16'''' M4 Build KIT M-LOK Black
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Brownells
Overview
The Brownells AR-15 M4 Build Kit features a complete upper assembly designed for the AR-15 platform, with a 16-inch barrel optimized for 5.56 NATO ammunition. This setup not only provides reliable performance but also allows for easy integration with various lower receivers, making it a versatile choice for your builds. You'll commonly find this upper receiver in tactical and general-purpose rifles, where a balance of maneuverability and effective range is desired.
Specifications
AR-15 M4 Build KIT M-LOK 5.56mm - AR15 16'''' M4 Build KIT M-LOK Black
Available Merchants(1)
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Stock Alert
Price and stock
The Brownells AR-15 M4 Build KIT M-LOK 5.56mm - AR15 16'''' M4 Build KIT M-LOK 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 $739.99 at Brownells for when it comes back.
Prices checked · refreshed daily across 37 retailers
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