The MFR XL Rail Systems from Daniel Defense utilize the M-LOK attachment system for incredible weight savings as well as superior cooling, ergonomics, and modularity while maintaining the strength and durability expected from Daniel Defense. M-LOK attachment points are located along the sides and bottom on the rail and feature an uninterrupted 1913 Picatinny rail on top. Its sleek bolt-up system increases strength and allows for easy installation. The increased internal diameter gives the operator the ability to attach a suppressor and have the proper clearance needed for installation. Anti-rotation tabs come standard for ease of installation and alignment. The MFR can be used with a pinned low-profile gas block on pistol, carbine, mid-length or rifle length gas systems.