AR-15 M4 Upper Receivers M-LOK 5.56mm - AR-15 16" M4 Complete Upper Assembly
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Brownells
Overview
The Brownells AR-15 M4 Upper Receiver is a complete assembly designed for the AR-15 platform, featuring a 16-inch barrel chambered in 5.56 NATO. This upper receiver provides a reliable and versatile option for builders looking to enhance their rifle with M4-style components. Commonly found in tactical and multi-purpose builds, this assembly offers a solid foundation for various applications, from home defense to recreational shooting.
Specifications
AR-15 M4 Upper Receivers M-LOK 5.56mm - AR-15 16" M4 Complete Upper Assembly
Available Merchants(1)
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Stock Alert
Price and stock
The Brownells AR-15 M4 Upper Receivers M-LOK 5.56mm - AR-15 16" M4 Complete Upper Assembly 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 $529.99 at Brownells for when it comes back.
Prices checked · refreshed daily across 37 retailers
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