Fortis REV II is an extremely lightweight yet robust free floating rail system. When designing the REV, Fortis didn't want just another rail system, they wanted a better, lighter, feature rich handguard that was robust and within budget. They've managed to reduce as much weight as possible while maintaining strength by utilizing a 1 piece body design. KeyMods were added at the 3, 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. Has anti-rotation tabs. Does Not Include Barrel Nut.