The continuous top rail allows you to mount iron sights, optics and any other accessories without additional rail sections. The M-Lok system allows users to customize the hand guard with rail sections and direct mount accessories. The hand guard is constructed of 6061-T6 aircraft aluminum and finished with a Mil-Spec type III hard coat black anodizing. 

The MLA free float handguard has a precision bore to fit the proprietary barrel nut which removes any unwanted play and ensure an exact fit!! Installation requires a 1-1/8" crows foot wrench (not included) for the barrel nut; standard AR-15 barrel nut wrenches will not work with this hand guard system. The hand guard is secured to the7075 aluminum barrel nut by 2 10/32 allen screws, stainless steel key seat lock, and anti-slip helicoils. Length is measured from along the top rail.

Link to parts manufacturer