DealGround Zero Precision's left handed upper receivers are manufactured for us in the United States by a major military and NASA contract to U. S. Military Specification. Forged from 7075 T-6 Aluminum and hard coat type III class III anodized in matte black for durability and reliability in the most extreme of environments. Manufactured to U. S. Mil-SpecForged 7075 T-6 AluminumM-4 Upper Receiver with M-4 Feed Ramps 1913 Picatinny Rail Flat Top with "T" positioning marksIncludes Forward Assist & Dust Cover - (Assembled)Left Handed Ejection Port and Forward AssistMulti-Caliber CapableHard Coat Anodize Type III Class II Matte Black Finish from Ground Zero Precision |