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Geissele Super Modular MK4 Rail w/ Gas Block (Options)

Geissele Automatics

  • The Super Modular Rail (SMR) MK4 M-LOK™ is Geissele’s ultra-lightweight M-LOK option. These rails are purpose-built and feature integrated M1913 picatinny rail sections at the fore of the rail in the 3, 6 and 9 o’clock positions. Maximum venting for heat dissipation also dramatically reduces the rail's overall weight, while maintaining its same strong and rigid platform. Utilizing Magpul's M-LOK technology at the 3, 6, and 9 o'clock positions, as well as the upper 45 quadrants. The SMR MK4 is both versatile and modular, allowing the user to tailor their platform to his or her unique needs. The SMR MK4 also features Geissele's proprietary 2" long barrel nut. This increases the surface contact where the rail interfaces with the receiver and creates a platform that can be trusted to be straight and true the entire length of the free float rail. This increases accuracy and zero repeatability during disassembly and reassembly when performing maintenance. Bundled with a low-profile Geissele Super Gas Block, a $59 value, the SMR MK4 is not only feature packed, but it is also value packed.
    - Available in 9.5", 13", or 15"
    - Black or Desert Dirt finish
    - Includes .750" Low Profile Stainless Steel Geissele Super Gas Block
    - Click Here to review our DDC (Desert Dirt Color) disclaimer before purchasing.

    NOTE: Our rails are designed to work with Mil-Spec M4 upper receivers. The compatibility with billet receiver sets is unknown.
  • Manufacturer Part Number: 05-283B (9.5" Black); 05-283S (9.5" Desert Dirt); 05-278 (13" Black); 05-278 (13" Desert Dirt); 05-315 (15" Black); 05-315 (15" Desert Dirt)

    Length Height: Length: ID*: OD*/DAQ*: Weight: Installed Weight (w/ Hardware):
    9.5" 2.3" 9.5" 1.35" 2.11" 9.3 oz. 11.2 oz.
    13" 2.3" 13" 1.35" 2.11" 11.0 oz. 12.9 oz.
    15" 2.3" 15" 1.35" 2.11" 13.1 oz. 15.0 oz.


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