The LWRC DI is a family of semi-automatic rifle chambered in a number of different calibers all utilizing LWRCs proprietary direct impingement system. Barrels are either 16.1 or 18.1 in length with a picatinny rail allowing users to attach their choice of optics. All LWRC DI models offer a number of ambidextrous features including a sling mount and charging handle.DetailsCALIBER 5.56 NATO - BARREL 16.1 40.9cm - WEIGHT 6.6lbs 2.9kg - OA LENGTH 32-35.25 81.3-89.5cm - MUZZLE THREADS 12 x 28 TPI - RIFLING 17 RH - LWRCI DIRECT IMPINGEMENT SYSTEM - LWRCI PROPRIETARY DI BOLT CARRIER GROUP - LWRCI MLOK FREE-FLOAT RAIL - FULLY AMBIDEXTROUS LOWER CONTROLS MAG RELEASE BOLT CATCHRELEASE SELECTOR - LWRCI ENHANCED FIRE CONTROL GROUP - LWRCI A2 BIRDCAGE FLASH HIDER - LWRCI AMBIDEXTROUS SLING MOUNT - LWRCI AMBIDEXTROUS CHARGING HANDLE - LWRCI ADJUSTABLE COMPACT STOCK - MAGPUL MOEGRIP