Daniel Defense's MFR rail systems utilize the M-Lok attachment system to offer impressive weight reduction, superior cooling, improved ergonomics and versatile modularity, all while upholding the renowned strength and durability of the brand. The rail features seven M-LOK attachment points, along with a continuous 1913 picatinny rail on top. Ambidextrous sling swivel attachment points are integrated into both sides of the rail for easy use. The rail's sleek bolt-up design enhances strength while minimizing its diameter, making it more comfortable to control. The inclusion of the bolt-up system barrel nut further increases its performance and anti-rotation tabs ensure easy installation and alignment. The MFR system is compatible with pinned low-profile gas blocks across all gas system lengths, including pistol, carbine, mid-length and rifle configurations. Lightweight free-floating barrel design Steel barrel nut Continuous mil-spec 1913 picatinny upper rail M-LOK attachment available at seven distinct positions Configurable sling swivel attachment points Bolt-up mounting system with patent protection Military specification grade 8 fasteners