


Product Description
The Geissele Automatics Super Modular Rail (SMR) MK4 M-LOK is an ultra-lightweight, free-float AR-15 handguard built for strength, rigidity, and modular accessory placement. Designed around Magpul M-LOK slots at the 3, 6, and 9 oclock positions (plus the upper 45-degree quadrants), it allows you to configure lights, grips, and other accessories exactly where you need them. Integrated short M1913 Picatinny rail sections at the fore end (3/6/9 oclock) add additional mounting flexibility, while extensive venting promotes heat dissipation without sacrificing the rails robust feel.
The MK4 uses Geisseles proprietary 2.25-inch long barrel nut to increase surface contact with the receiver for a straight, true interface that supports accuracy and repeatable zero after maintenance. Installation requires a Geissele barrel nut wrench (sold separately). Finished in black and built to demanding standards, the SMR MK4 is a versatile choice for hard-use AR builds.
Product Highlights
- Free-float Super Modular Rail (MK4) design enhances rigidity and supports consistent accuracy and repeatable zero
- M-LOK accessory mounting at 3, 6, and 9 oclock plus upper 45-degree quadrants for highly modular setups
- Integrated short M1913 Picatinny rail sections at the fore (3/6/9 oclock) for secure accessory mounting
- Maximum venting helps dissipate heat while keeping overall weight low
- Includes Geissele proprietary 2.25-inch long barrel nut (barrel nut wrench sold separately)
Specs
- Brand: Geissele Automatics
- Model/Series: Super Modular Rail (SMR) MK4
- Mount Type: M-LOK
- Handguard Type: Free-Float
- Length: 13.5 in
- Integrated Rail Sections: Short M1913 Picatinny sections at fore in 3/6/9 oclock positions
- Height: 2.4 in
- Inner Diameter: 1.35 in
- Outer Diameter: 2.11 in
- Weight (with hardware): 13.5 oz
- Material: 6061-T6 Aluminum
- Finish: Type III Hardcoat Anodized (Black)
- Included: Barrel nut (barrel nut wrench sold separately)
- Compatible Platform: AR-15 (Mil-Spec M4 upper receivers)
- Country of Origin: USA
- UPC: 854014005717
- Manufacturer Part Number: 05-278B
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