Spikes Tactical STU5435MLS 5.56 NATO 16″ Complete Upper

The Spikes Tactical STU5435MLS is a complete AR-15 upper assembly built around a 16″ cold hammer forged barrel chambered for .223 REM/5.56 NATO. It ships as a factory-assembled unit with a mid-length gas system and a 12″ SAR3 free-floating handguard for improved accessory integration. The upper includes an A2 front sight and A2 flash hider, and the receiver is finished in black 7075-T6 aluminum. Components are produced to Mil-spec standards for compatibility with standard AR rifles.

Key Specifications

• The caliber is .223 REM/5.56 NATO.
• The barrel length is 16 inches.
• The barrel finish is Black Phosphate.
• The barrel description is Mid-Length Cold Hammer Forged.
• The rate of twist is 1:7.
• The gas system is Mid Length Gas System.
• The handguard is a 12″ SAR3 Free-Floating unit.
• The receiver is 7075-T6 Aluminum, black.
• The front sight is an A2 Front sight.
• Included accessory is an A2 Flash Hider.

As a drop-in complete upper, the STU5435MLS streamlines upgrades and builds by combining a durable cold hammer forged barrel, a proven mid-length gas system, and a free-floating handguard in a factory-assembled package. Its mil-spec components support reliable operation and straightforward installation for a wide range of shooting roles, making it a practical choice for those assembling or improving an AR platform.