Fortis REV™ is an extremely lightweight yet robust free floating rail system. When designing the REV™, we didn’t want just another rail system, we wanted a better, lighter, feature rich handguard that was robust and within budget. We’ve managed to reduce as much weight as possible while maintaining strength by utilizing a 1 piece body design. KeyMods were added at the 6 & 9 o'clock positions for modularity and additional weight savings. Its unique mounting system captures a standard AR15 barrel nut for easy installation. Check out all the features and see for yourself why the Fortis REV™ beats the competition. It is also piston compatible. Because of the anti-rotational tabs, the REV™ rail may not fit all uppers without slight modification. Fits most mil-spec forged uppers without any issues. Features: Material: Aircraft Grade 6061-T6 Aluminum Finish: Military Specification Type III Hard Coat Anodized Length: 12.429" Weight 9.2 Ounces Inside Diameter: 1.340" Contiguous Top Rail Rotation Limited QD Sockets KEYMOD at the 3 & 9 O’clock Anti-Rotation Tabs (Fits Forged Uppers) Uses Standard AR15 Barrel Nut (Not Included) Made in the USA!