The LWRCI Di is made with the same craftsmanship and design excellence that comes with every LWRCI firearm and now available with LWRCI specified M-LOK� Rail. Built from the ground up to be more than just another direct impingement rifle the LWRCI Di delivers the quality every rifle enthusiast demands with innovation that's expected from LWRCI. - High Performance features like fully ambidextrous controls monoforged upper receiver with modular M-LOK� one-piece free float rail LWRCI Cold Hammer Forged Nicor-treated spiral fluted barrel. (NOTE: Spiral Fluted Barrels only on 16.1 barrel lengths) Our innovative keyless bolt carrier design combined with an operating system that is time-tested makes the DI the perfect addition to the LWRCI lineup and your gun cabinet. And since the full ambidextrous lower receiver is compatible with the rest of our IC family you can upgrade your Di to our flagship piston-driven IC just by switching out the upper. - CALIBER: 5.56 NATO - BARREL: 16.1 [40.9cm] - WEIGHT: 6.6lbs [2.9kg] - O/A LENGTH: 32-35.25 [81.3-89.5cm] - MUZZLE THREADS: 1/2 x 28 TPI - RIFLING: 1:7 RH