Spikes STU5435R2S Complete Upper 5.56x45mm NATO 16" Black Phosphate/Midlength Barrel, 7075-T6 Aluminum Black Receiver, 12" SAR3 Free-Floating Handguard for AR-15

The Spikes STU5435R2S Complete Upper 5.56x45mm NATO 16" Black Phosphate/Midlength Barrel is a purpose-built upper receiver assembly designed for AR-15 platforms demanding reliability in tactical, law enforcement, and precision shooting applications. This complete upper eliminates the need for time-consuming assembly and headspacing verification, delivering a drop-in solution ready for immediate deployment. Whether you're building a duty rifle, home defense platform, or precision carbine, this Spikes upper offers the quality and performance expected by professionals who depend on their equipment under pressure.

Built around a 7075-T6 aluminum receiver in mil-spec black, this upper delivers the durability and corrosion resistance required in demanding environments. The 16-inch black phosphate-finished barrel in midlength gas system strikes the optimal balance between velocity, controllability, and tactical handling—a length favored by law enforcement and military units for its versatility in CQB and intermediate-range engagements. The 12-inch SAR3 free-floating handguard decouples barrel harmonics from external mounting points, enhancing accuracy and consistency shot-to-shot.

The complete assembly weighs 5.15 pounds, maintaining a responsive feel during dynamic shooting while preserving repeatability. This upper receiver assembly is compatible with standard AR-15 lower receivers, making it an excellent choice for those looking to upgrade or build their rifles. With its robust construction and thoughtful design, the Spikes STU5435R2S is ideal for anyone seeking a reliable and high-performing upper receiver.