YHM is very pleased to offer our flagship BLACK DIAMOND� Specter XL Top End. The Diamond forearm bridges the gap between the upper receiver and handguard and is marked for position on all 4 sides. YHM's diamond pattern in the hand guard reduces weight and blends perfectly with our diamond fluted barrels. - Specifications - Chambering: 5.56mm - Twist Rate: 1:7 - Forged 7075-T6 Flat Top Upper Receiver with M4 Feed Ramps and T marked - Forward Assist - Includes Charging Handle - Includes Bolt Carrier Assembly - 16 4140 Steel Barrel Heat Treated to RC 25-32 - Diamond Fluted to Improve Rigidity and Aid in Barrel Cooling - Threaded to take our Popular Muzzle Accessories - YHM Phantom 5C2 Flash Hider / Compensator - YHM 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) - Includes all Internal Parts - Total Weight: 4.8 lbs.