Fortis Manufacturing's REV II AR-15 M-Lok 14"" Free Float Rail System is an extremely lightweight yet robust free floating rail system. When designing the REV(TM)"" they 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. M-Lok cutouts were added 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(TM) beats the competition. It is also piston compatible. Has anti-rotation tabs.