Featuring the same industry leading barrel nut and lock up design as originally introduced on BCM's evolutionary KMR handguard, the MCMR Series of handguards gives the shooter modularity in the M-LOK® platform. This proprietary patented mounting system (US Patent 8904691), includes a mechanical index to the 12:00 rail and positions mounting hardware to mitigate the movement caused by heat generated by the weapon system.  MCMR features M-LOK® Compatible mounting system.Free Float Handguard eliminates loads from barrel, reducing the deflection for more accurate shooting.Precision Machined Aerospace 6061-T6 Aluminum Alloy, for high strength and lightweight.Proprietary engineered profile offers additional cross sectional strength.Steel Barrel Nut (same KMR, MCMR, and QRF series), to resist movement under heat.Hard Coat Anodized per Mil-A-8625F, Type III, Class 2Handguard alone weighs 4.8 ozHandguard mounting hardware 2.3 oz1.3” Inside Diameter1.5" WideDesigned to be used with mid length with a FSB or a carbine gas system with a low profile gas block.The barrel nut will fit over all mil-spec diameter barrels (max of 1")