Rock River Arms Mountain Pistol 10.5in Upper Black. 5in Upper. Formulated by using some of the very most strong and dependable components in existence these AR15 Upper Receivers from Rock River Arms offers you something that gives you many years of consistency. Rock River Arms has been making top quality merchandise for a number of years and the Rock River Arms Mountain Pistol 10.5in Upper is their particular approach to revealing how much they are concerned. Right here at OpticsPlanet we make it our responsibility to receive the perfect solution for all of your preferences and showcasing the Rock River Arms Mountain Pistol 10.5in Upper is one thing that we're happy to offer. Specifications for Rock River Arms Mountain Pistol 10.5in Upper: Manufacturer: Rock River Arms Caliber: 5.56x45mm NATO Overall Length: 20 in Barrel Length: 10.5 in Barrel Profile: Standard Gas System Length: Pistol Length Barrel Twist Rate: 1-7 Threads per Inch: 1/2x28 Muzzle Device: A2 Flash Hider Color: Black Gun Model: Universal Fabric/Material: Stainless Steel Handguard Length: 9.5 in Gun Rail: Full Top Rail Weight: 4 lb Magazine Included: No Package Contents: Rock River Arms Mountain Pistol 10.5in Upper Bolt Carrier Group Charging Handle Assembly What firearm models does the manufacturer say Rock River Arms Mountain Pistol 10.5in Upper is compatible with? The manufacturer says that Rock River Arms Mountain Pistol 10.5in Upper is compatible with UniversalRock River Arms MT0364: Mountain Pistol 10.5in Upper Black