will not ring upon firing or when struck, and is compatible with the Knight’s line of 5.56mm QDC Signature Reduction Devices.Folding 200-600 meter Micro Rear Sight and Micro Front Sight, Magpul MLOK Rail Covers, a Keymod Picatinny Rail (5 Slot), and a Kinght's Armament Buffer (4.6 oz...