**The Maxim PDX U.R.G ships with your choice of a Standard Mil-Spec BCG to be used with most common M4 compatible lowers, or a PDX/SCW compatible BCG buffer and Spring.  The Maxim Defense PDX™ U.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 PDX™ U.R.G. is the ultimate choice for when concealment and personal defense is non-negotiable. The PDX™ U.R.G. is also equipped with Maxim’s HATEBRAKE™ Muzzle 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. The PDX U.R.G. uses a Direct Impingement system. Specifications for Maxim Defense Industries PDX U.R.G. Mil-Spec 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 Model: AR-15 Weight: 4 lb Additional Features: Standart Mil-Spec Condition: New Magazine Included: No Country of Origin: USA Features of Maxim Defense Industries PDX U.R.G. Mil-Spec 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 Mil-Spec BCG or PDX/SCW compatible BCG Optimized Personal Defense Weapon Upper Increased reliability due to included HATEBRAKE Optimized low flash Designed to work with any Mil-Spec lower receiver Package Contents: Maxim Defense Industries PDX U.R.G. Mil-Spec Upper Receiver Maxim Defense Industries MDX 505 Mil-Spec 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 Mil-Spec BCG