Geissele Near Clone Upper Receiver Assembly 5.56mm 11.5in Barrel Low Profile 1-7 Twist Sand 11.5in. Barrel lengths and buttstocks have changed but more or less the evolution of Americas right arm has proceeded apace with each generation of warrior making her their own. In that time the sight of the M16/M4 in the competent grasp of young Americans has meant hope to countless millions of people around the globe. Specifications for Geissele Near Clone 11.5in 5.56mm Upper Receiver Assembly: Manufacturer: Geissele Caliber: 5.56mm Barrel Length: 11.5 in Gas System Length: Carbine Length Barrel Twist Rate: 1-7 Muzzle Device: Flash Hider Color: Sand Gun Model: AR-15 Condition: New Fabric/Material: Aluminum Gas Block Journal Size-Diameter: .750 in Gun Type: Rifle Gun Make: AR Platform Bolt Carrier Group Included: MIL-SPEC Magazine Included: No Package Contents: Geissele Near Clone 11.5in 5.56mm Upper Receiver Assembly What firearm models does the manufacturer say Geissele Near Clone 11.5in 5.56mm Upper Receiver Assembly is compatible with? The manufacturer suggests that Geissele Near Clone 11.5in 5.56mm Upper Receiver Assembly is compatible with AR-15Geissele 08-315: Near Clone Upper Receiver Assembly 5.56mm 11.5in Barrel Low Profile 1-7 Twist Sand 11.5in