Product Description The FightLite Industries MCR (Mission Configurable Rifle) Dual-Feed Upper Receiver Assembly is a groundbreaking drop-on MIL-Spec upper that transforms any AR-15/M16/M4-compatible lower receiver into a belt-fed or magazine-fed platform without permanent modification. Chambered in 5.56x45mm NATO and featuring a 16.25" quick-change, chrome-lined barrel threaded 1/2x28, this upper receiver is precision machined from 7075-T6 billet aluminum and features a short-stroke gas piston operating system for enhanced reliability. The M-LOK handguard provides versatile accessory attachment, while the manganese phosphate and Type III, Class 2 hardcoat anodize finish deliver maximum corrosion and wear resistance. Dry Film Lubrication is applied to critical high-friction surfaces for outstanding performance in extreme conditions. Compatible with AR-15/M16 magazines and M27 linked ammunition, the MCR556DFRM ships with a comprehensive accessory package and is proudly made in the U.S.A. Product Highlights Dual-Feed Versatility: Accepts all AR-15/M16 standard magazines as well as M27 belt-linked ammunition, offering unmatched operational flexibility. Short-Stroke Gas Piston Operation: Provides reliable, consistent cycling and reduces fouling in the receiver compared to direct impingement systems. Precision 7075-T6 Billet Construction: Upper receiver, feed cover, and charging handle are precision machined from aerospace-grade 7075-T6 billet aluminum for exceptional strength and durability. Dry Film Lubrication: Applied to critical high-friction surfaces, enhancing performance and longevity under extreme operating conditions. Complete Ready-to-Run Package: Ships with Belt-Feed Main Action Spring, MIL-Spec H3 Buffer, Carbine Stock Spacer, Extended Bolt Catch, Mag Adapter, RIPBrake Muzzle Compensator, 100 M27 Links, and Operator&';s Manual. Specs Brand: FightLite Industries MPN: MCR556DFRM UPC: 859714006910 Caliber: 5.56x45mm NATO Barrel Length: 16.25" Barrel Twist: 1:7" RHT Barrel Threading: 1/2x28 TPI Barrel Finish: Chrome Lined Receiver Material: 7075-T6 Billet Aluminum Handguard Style: M-LOK Operating System: Short-Stroke Gas Piston Bolt Carrier: Full-Auto Finish: Manganese Phosphate and Type III, Class 2 Hardcoat Anodize Black Dry Film Lubrication: Applied to critical high-friction surfaces Feed System: Dual-Feed (Magazine and Belt) Compatible Magazines: All AR-15/M16 Magazines and M27 Linked Ammunition Sights: Adjustable Sight Set Included Color: Black Country of Manufacture: USA Includes: Belt-Feed Main Action Spring, MIL-Spec H3 Buffer, Carbine Stock Spacer, Extended Bolt Catch, Mag Adapter, RIPBrake Muzzle Compensator, (100) M27 Links, Operator&';s Manual Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer. ]]>