The Super Modular Rail 13.5" (SMR) MK16 M-LOKA(R), NSN# 1005-01-672-4794 (13.5"), has been adopted by USASOC for the URG-I program (Upper Receiver Group Improved). The Geissele Super Modular Rail MK16 offers unmatched performance for the most demanding shooters. Mounted to your AR-15 upper using the updated version of the proven Geissele Barrel Nut design, the MK16 is not only easy to install and maintain but offers superior rigidity. Anti-rotation tabs and set-screws ensure that your rail will won't rotate, even under the most extreme conditions of use. M1913 picatinny rail on top and M-LOK(TM) slots on every quadrant ensures maximum customization for all your ac Mfg: Geissele Automatics