Daniel Defense manufactures the highest quality complete AR15 upper receivers on the market today! Every Daniel Defense upper is painstakingly hand assembled, quality assurance tested, and test fired to ensure that the highest quality product makes it to the hands of our customers. The Daniel Defense M4 URG, MK18 comes complete with bolt carrier group and charging handle, 10.3? Cold Hammer Forged Barrel, RIS II MK18 Rail System in Black or Flat Dark Earth, and Daniel Defense low profile gas block.MK18, URG, 10.3" 5.56, 1:7 Twist, GOV, LPG, RIS II Rail, DDFS-Black. Upper receiver is Mil-Spec with Indexing Marks and M4 Feed Ramps. CNC Machined of 7075-T6 Aluminum, Type III Hard Coat Anodized. Barrel is Chrome Moly Vanadium Steel, Cold Hammer Forged, 1:7 twist, 10.3? Government Profile, Chrome Lined, MP tested, and Mil-Spec Heavy Phosphate Coated. Gas System is Pinned Low Profile Gas Block CNC Machined of 4140 hardened steel with Mil-Spec Heavy Phosphate Coating, Carbine Length, Direct Impingement. Daniel Defense Flash Suppressor, 17-4 PH Stainless Steel, Salt Bath Nitride Finished. BCG M16 Profile, Mil-Spec MP Tested, Chrome Lined, Properly Staked Gas Key. Handguard is Daniel Defense RIS II MK18, CNC Machined of 6061-T6 Aluminum, Type III Hard Coat Anodized. Daniel Defense Rail Panels made from Santoprene, heat resistant to 300° F. Specifications for Daniel Defense MK18, URG, 10.3in 5.56 Complete Upper Receiver w/ Flash Hider: Manufacturer: Daniel Defense Cartridge: 5.56x45mm NATO Barrel Length: 10.3 in Barrel Twist Rate: 1-7 Finish: Type III Hard Coat Anodized Gun Model: AR-15 Condition: New Gun Rail: RIS II Rail Additional Features: w/ Flash Hider Weight: 3.8 lb Magazine Included: No Features: 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, 10.3" Government 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, Carbine Length, Direct Impingement MUZZLE DEVICE: Daniel Defense Flash Suppressor, 17-4 PH Stainless Steel, Salt Bath Nitride Finished BOLT CARRIER GROUP: M16 Profile, Mil-Spec MP Tested, Chrome Lined, Properly Staked Gas Key SIGHTS: Sold Separately HANDGUARD: Daniel Defense RIS II MK18, CNC Machined of 6061-T6 Aluminum, Type III Hard Coat Anodized CHARGING HANDLE: GRIP-N-RIP Charging Handle, Body CNC Machined of 7076-T6 Aluminum, Handles & Latch CNC Machined of 6061-T6 Aluminum, Heavy Duty Stainless Steel Roll Pins, Type III Hard Coat Anodized RAIL PANELS: Daniel Defense Rail Panels Made from Santoprene, Heat Resistant to 300 degrees F. Package Contents: Daniel Defense MK18, URG, 10.3in 5.56 Complete Upper Receiver w/ Flash Hider Daniel Defense Warranty: Guaranteed Satisfaction All Daniel Defense products carry a 100% satisfaction guarantee against defects in original materials and workmanship. If your Daniel Defense product shows evidence of such defects, Daniel Defense will make every accommodation to fix, repair, or replace your product in the most expeditious manner possible. Daniel Defense does not warranty products or damage caused to our products by the correct or incorrect installation of other manufacturer's products. Warranty information and warranties are supplied solely by the manufacturer, and not this retailer. This retailer publishes information from the manufacturer for information purposes only, and the manufacturer is solely responsible and liable for any warranty information and warranties published by this retailer. Please reference the appropriate manufacturer documents or reach out to the manufacturer directly for full warranty terms and effective dates. @media screen and (max-width: 400px) { #w-block-one { display:table-row !important; } }