KDG (Kinetic Development Group)
KDG (Kinetic Development Group) builds the aftermarket rail and mounting systems that turned the FN SCAR into a fully modular rifle platform. The MREX M-Lok handguard family replaces the SCAR's proprietary rail with true M-Lok real estate in multiple lengths, and the Sidelok quick-detach optic mount system delivers return-to-zero reliability for red dots and magnifiers. KDG also builds charging handles, muzzle extensions for the Grand Power Stribog, and general M-Lok rail sections and QD mounts for any M-Lok-compatible rifle.
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What Is KDG (Kinetic Development Group)?
KDG is best known as the go-to aftermarket parts maker for the FN SCAR platform, building the rail systems and optic mounts that turned a fairly proprietary rifle into a fully modular one. Its Sidelok optic mount line and M-Lok hardware also extend well beyond the SCAR to any rifle running M-Lok handguards.
KDG SCAR MREX M-Lok Handguards
The MREX MK2 handguard replaces the FN SCAR's factory rail with a full M-Lok system, available in 2.2", 4.25", and 6.5" lengths beyond the upper receiver. M-Lok slots run the full length of the handguard, including 2 and 10 o'clock positions shielded from the gas block, so a SCAR 16S or 17S can mount lights, grips, and bipods anywhere the shooter needs them instead of being limited to factory rail sections.
KDG Sidelok Optic Mounts
The Sidelok mount is a quick-detach optic mounting system built for return-to-zero reliability — the mount rolls onto the rifle from the hard side, then locks down to hold position precisely every time it's reinstalled. Sidelok mounts are available for Trijicon MRO, Aimpoint, and RMR-pattern optics in both 30mm and 34mm sizes, letting a shooter swap an optic between rifles without losing zero.
KDG SCAR Charging Handles and Muzzle Extensions
The Scarging Handle is KDG's charging handle upgrade for SCAR rifles running non-reciprocating charging handle (NRCH) uppers, built in black and flat dark earth. KDG also makes the SMX3 and SMX6 muzzle extensions, which add reach for the Grand Power Stribog SP9 pistol carbine and similar platforms that need a longer barrel profile for compliance or balance.
KDG General M-Lok Hardware and Accessories
Beyond SCAR-specific parts, KDG sells general-purpose M-Lok hardware — QD sling mount adapters, 3-slot M-Lok Picatinny rail sections, and the Kinect GoPro mount — that work on any M-Lok-compatible handguard, not just the SCAR. The Optics HUB spotting scope case rounds out the catalog for shooters who need rugged storage for precision optics in the field.
Frequently Asked Questions
What rifles does KDG make parts for?
Primarily the FN SCAR 16S and SCAR 17S, though KDG's M-Lok hardware and Sidelok optic mounts work on any compatible rifle, and its muzzle extensions fit the Grand Power Stribog.
What does the Sidelok mount do differently from a standard optic mount?
It rolls onto the rifle from the hard side and locks down, designed to return an optic to the same zero every time it's reinstalled — useful for shooters who swap one optic between multiple rifles.
What's the difference between the MREX MK2 lengths?
The 2.2", 4.25", and 6.5" options refer to how far the handguard extends beyond the SCAR's upper receiver — longer options give more rail space for accessories.
Does KDG make anything for non-SCAR rifles?
Yes — its M-Lok rail sections, QD mounts, and Sidelok optic mounts are general-purpose and fit any compatible M-Lok handguard or optic footprint.