The M4A1 RIII AR15 style firearm features a fully ambidextrous lower that allows both left- and right-handed shooters to operate the bolt catch safety selector and magazine release without having to move or remove their dominant hand from the rifle’s grip. Its GRIP-N-RIP Charging Handle is ambidextrous as well. We’ve taken the RIS II picatinny quad rail used on our M4A1 original and replaced it with a 12.5 inch RIS III rail featuring M-LOK attachment for lighter weight while still offering M203 grenade-launcher attachment. The M4A1 RIII is built around a 14.5 inch Cold Hammer Forged Government Profile barrel with a permanently attached Daniel Defense Flash Suppressor. This rifle also comes with the ergonomic Daniel Defense Buttstock and Pistol Grip. – MATERIALS & CONSTRUCTION LOWER RECEIVER: Proprietary with Enhanced Flared Magazine Well Fully Ambidextrous Controls and Rear Receiver QD Swivel Attachment Point. CNC Machined of 7075-T6 Aluminum Type III Hard Coat Anodized – UPPER RECEIVER: Mil-Spec with Indexing Marks and M4 Feed Ramps. CNC Machined of 7075-T6 Aluminum Type III Hard Coat Anodized – BARREL: Chrome Moly Vanadium Steel Cold Hammer Forged 1:7 Twist 14.5 M4 Profile Chrome Lined Mil-Spec Heavy Phosphate Coated and HP/MPI Tested – GAS SYSTEM: Pinned Low Profile Gas Block CNC Machined of 4140 Hardened Steel with Mil-Spec Heavy Phosphate Coating Mid-length Direct Impingement – MUZZLE DEVICE: Pinned and Welded Daniel Defense Flash Suppressor Extended 17-4 PH Stainless Steel Salt Bath Nitride Finished – BOLT CARRIER GROUP: M16 Profile Mil-Spec MP Tested Chrome Lined Properly Staked Gas Key – BUFFER: H Buffer – SIGHTS: Sold Separately – HANDGUARD: Daniel Defense RIS III 12.5 Patented 6-Bolt Bolt-Up System Flat Dark Earth CNC Machined of 6061-T6 Aluminum – CHARGING HANDLE: GRIP-N-RIP Charging Handle Body CNC Machined of 7075-T6 Aluminum Handles & Latch CNC Machined of 6061-T6 Aluminum Heavy Duty Stainless Steel Roll Pins Type III Hard Coat Anodized – RECEIVER EXTENSION: 6 Position Mil-Spec 7075-T6 Aluminum – BUTTSTOCK: Daniel Defense Buttstock Glass Filled Polymer with Soft Touch Overmolding – PISTOL GRIP: Daniel Defense Pistol Grip Glass Filled Polymer with Soft Touch Overmolding Made in the USA! – Specifications – Mounting System M-LOK – Caliber 5.56mm NATO – Muzzle Thread 1/2 × 28 TPI (Threads Per Inch) – Gas System Mid-length – Barrel Length 14.5 – Barrel Profile M4 – Product Weight 6.39 lbs – Length 31 1/2-34 ¾ – Magazine DD Magazine – Case Daniel Defense Full-Latch Impact Plastic Case