The Troy MRF-DI is a non-free floating direct replacement for all AR15 Mid Length plastic hand guards. The Troy Patented clamping design ensures absolute rock solid mounting which is unequalled in the world today. The MRF-DI provides a true optical mounting platform that increases the modularity and accuracy of the AR15. No gunsmithing is required as the MRF-DI installs in less than a minute and provides true U.S. Military Specification M1913 rails at 12-3-6 and 9 o'clock. All MRF rail systems are machined from hardened aircraft aluminum and finished in MIL-STD Type III Hard Coat Anodize in Flat Black. Made in USA. Easy Install.