Daniel Defense M4A1 FSP Upper Receiver 14.5" Pinned/Welded 5.56 NATO – AR-15 Lower (FDE)

The Daniel Defense M4A1 FSP Upper Receiver delivers a 14.5-inch cold hammer-forged barrel in 5.56 NATO with a permanently attached muzzle device to meet the 16-inch legal requirement. This configuration features a fixed front sight post (FSP) and mil-spec profile, designed to drop onto any mil-spec AR-15 lower receiver. Flat Dark Earth Cerakote finish.

Upper receiver and barrel extension are CNC-machined from 7075-T6 aluminum with M4 feed ramps. The barrel is chrome-lined with a 1:7 twist rate and M4 profile contour under a mid-length gas system. Comes with BCG, charging handle, and Daniel Defense furniture. No gunsmithing required for installation on a standard AR-15 lower.

• Caliber: 5.56 NATO
• Type: Complete upper receiver assembly
• Compatible Lower: Mil-spec AR-15
• Barrel Length: 14.5 inches (pinned/welded to 16")
• Material: 7075-T6 aluminum receiver, cold hammer-forged barrel
• Finish: Flat Dark Earth Cerakote
• Includes: BCG, charging handle, handguard, fixed front sight post
• Installation: Drop-in to mil-spec AR-15 lower, no gunsmithing needed