Action: Semi-Auto - Caliber: 5.56 NATO - Capacity: 30rd - Barrel: 16 (1:7) Fluted with Phantom 5C2 Flash Hider - Sights: Flip - Receiver Upper: 7075-T6 Aluminum Black - Receiver Lower: 7075-T6 Aluminum Black - Stock: Adjustable - Handguard: Specter XL (Rifle Length) Diamond - Weight: 6.9 lbs. - T Marked Upper Receiver - 16 4140 Steel Barrel Heat Treated to RC 25-32 - YHM Diamond Fluting Improves Rigidity and Aids in Barrel Cooling - YHM Phantom 5C2 Flash Hider / Compensator - YHM Specter XL (Rifle Length) Diamond Handguard (YHM-9635-DX) - YHM Forearm Endcap (YHM-9484-A) - YHM Low Profile Gas Block (YHM-9384) - YHM Forearm Mounted Flip Front Sight (YHM-9627) - YHM Flip Rear Sight (YHM-9680) - Adjustable Commercial Carbine Stock - Includes all Internal Parts - YHM is very pleased to offer the YHM-8820 Black Diamond Specter XL. Chambered in 5.56mm 6.8 SPC or .300 BLK with many of our premium accessories built in. Our Diamond series handguard bridges the gap between the upper receiver and hand guard and is marked for position on all 4 sides. The Diamond pattern in the hand guard reduces weight and blends nicely with our diamond fluted barrels.