The Colt M4 Upper 5.56 11.5" LW BLK, model LE6933CK, is a complete AR-15 upper receiver assembly built around an 11.5" lightweight barrel chambered in 223 Remington / 5.56 NATO. It features a flat-top receiver with Picatinny rail, A2 fixed front sight, and a Magpul backup rear sight, giving shooters a dependable sighting system right out of the box. The upper includes an A2 flash hider and polymer handguard, delivering a classic M4-style profile with modern reliability.

This upper receiver is well suited for training, range use, and building a compact AR-15 configuration where a shorter barrel is desired and legally permitted. The direct impingement operating system, M4 free-floating barrel, and Type III hard coat finish are designed to provide consistent performance and long service life. Colt’s long-standing reputation for precise manufacturing and durable components makes this upper a solid choice for shooters who value proven design and dependable craftsmanship.

Key Features:

• Manufacturer: Colt
• Model: LE6933CK M4 Upper
• Caliber: 223 Remington / 5.56 NATO
• Barrel Length: 11.5" Lightweight
• Front Sight: A2 Fixed Front Sight
• Rear Sight: Magpul Backup Rear Sight
• Gas System Length: Carbine
• Operating System: Direct Impingement
• Muzzle Type: A2 Flash Hider
• Receiver Type: Flat-Top With Picatinny Rail
• Handguard: Polymer