American Tactical Imports AR15 Omni Hybrid Maxx features a fully-patented metal reinforced polymer upper receiver along with a fully-patented metal reinforced polymer lower receiver. The Omni Hybrid lower features a patented hammer and trigger pin retainment system, preventing movement from the hammer and trigger pin during firing. The Omni Hybrid also featured our patented over-molded metal insert, which reinforces the buffer tube housing and rear takedown pin. This allows for metal-on-metal contact with both the buffer tube as well as the rear takedown pin thus increasing strength and durability from recoil and consistent firing. In addition a magazine is now included with all Omni Hybrid MAXX pistols. Features: - Omni Hybrid MAXX Polymer Upper Receiver with Metal Insert - Omni Hybrid Polymer Lower Receiver with Metal Insert - Low Profile Gas Block - Flat Top, Optics Ready Specifications: - Caliber: 5.56 / .223 - Barrel Length: 7 1/2" Black Nitride Coated - Capacity: 30 Rounds - Number of Magazines: 1 - Free Float Rail: 7"