Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver 300 BLK NATO Hate Brake 5/8-24 Thread 5.5in Barrel Arid Earth. R.G is built to handle the fierce demands of the Tier 1 community and designed to install on any Mil-Spec lower receiver. With the PDX U.R.G you dominate close quarter encounters and achieve maximum energy on target without sacrificing accuracy at distance. At just 14 in overall length and a 5.5 barrel the PDXU.R.G. is the ultimate choice for when concealment and personal defense is non-negotiable. The PDXU.R.G. is also equipped with newly invented Maxim HATEBRAKEMuzzle Booster. This patent-pending device significantly reduces recoil decreases the flash signature pushes gasses and concussion waves downrange away from the operator improving overall execution in short barrel pistols and rifles. The PDX U.R.G. uses a Direct Impingement system. Ships with a PDX/SCW compatible bolt carrier group. Specifications for Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver: Manufacturer: Maxim Defense Industries Overall Length: 14 in Barrel Length: 5.5 in Handguard Type: Free-Float Muzzle Device: Hatebrake Finish: Type III Hardcoat Anodized Fabric/Material: 6AL-4V Titanium 6061 Aluminum 7075 Aluminum 17-4 Stainless Steel Gun Rail: Picatinny Gun Type: Rifle Gun Model: AR-15 Weight: 4 lb Additional Features: PDX/SCW Compatible Condition: New Magazine Included: No Country of Origin: USA Package Contents: Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver Package Contents: Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver HATEBRAKE installed under handguard M-slot compatible handguard Military grade materials 6Al-4V Titanium 17-4 Stainless Steel 7075 and 6061 Aluminum HK height rail for a more rigid upper receiver Maxim PDX/SCW compatible BCG What firearm models does the manufacturer say Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver is compatible with? The manufacturer suggests that Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver is compatible with AR-15Maxim Defense Industries MXM-47836: MDX 505 PDX/SCW Compatible URG Upper Receiver 300 BLK NATO Hate Brake 5/8-24 Thread 5.5in Barrel Arid Earth