The Geissele Automatics Super Modular Rail (SMR) MK4 M-LOK represents the company’s most robust M-LOK handguard option. Built with integrated M1913 picatinny rail sections at the 3, 6, and 9 o’clock positions, the rail delivers versatility right out of the box. Extensive venting reduces weight without sacrificing the rigid, strong platform that defines this design.
M-LOK slots are positioned at the 3, 6, and 9 o’clock positions as well as the upper 45 quadrants, letting you configure your setup to match your specific needs. Geissele’s proprietary 2.25″ long barrel nut expands the surface contact area where the rail meets the receiver, establishing a dependable platform that stays true across the entire free float length. This interface design supports both accuracy and zero repeatability through maintenance cycles and reassembly.
