Griffin Armament M4SD 3-Prong Flash Hider Suppressor Adapter, 1/2"-28 Thread, 5.56mm, Stainless Steel Nitride

The Griffin Armament M4SD 3-Prong Flash Hider is a precision-engineered muzzle device designed for AR-pattern carbines and rifles in 5.56mm. Built for shooters who run suppressors, this adapter serves dual duty: it tames muzzle flash while functioning as the quick-detach interface for Griffin's M4SD suppressor series (M4SD2, M4SDK, 30SD, and 30SDK). If you're building a short-barrel rifle or running a suppressed setup where flash reduction and compact profile matter, the M4SD gives you a high-performance alternative to standard birdcage flash hiders without sacrificing shooter control.

Griffin engineered this generation 3 design with flash reduction as the priority. The three-prong geometry is CNC-machined and precisely ported to neutralize muzzle rise while minimizing the bright signature that gives away your position. The prongs are optimized to reduce ringing and pinging—a hallmark of poorly designed flash hiders—so you get clean sound suppression characteristics, especially when paired with a suppressor. The whole unit is machined from precipitation-hardened 17-4 stainless steel and finished in black nitride, a coating that stands up to the corrosion and wear that comes with hard use and frequent disassembly.

The M4SD accepts standard 1/2"-28 threads, the industry norm for 5.56mm carbines, and includes a shim set to dial in your fit. It ships with an over-travel stop washer that locks into position—mount it at 6 o'clock to prevent over-rotation when mating with your suppressor. The design is pre-drilled for pinning and welding, so if you're building a 14.5" barrel carbine and want to meet the 16" overall length requirement without NFA registration, this will handle that job. The ambidextrous quick-detach mount makes swapping your suppressor on and off fast and repeatable.

Key Features

• Dual-use flash hider and M4SD suppressor quick-detach adapter
• Three-prong design with precisely calculated porting to reduce muzzle rise and flash signature
• 17-4 precipitation-hardened stainless steel with black nitride finish for durability and corrosion resistance
• Optimized geometry eliminates ringing and pinging common in poor flash hider designs
• 1/2"-28 thread pitch fits standard 5.56mm AR-pattern barrels
• Includes shim set for fitment adjustment and over-travel stop washer
• Pre-drilled for pinning and welding to 14.5" barrels for legal 16" OAL carbines
• Ambidextrous quick-detach mount for fast suppressor attachment and removal

Specifications

Frequently Asked Questions

Will the Griffin M4SD flash hider work with my suppressor?

The M4SD 3-Prong Flash Hider is specifically designed as an interface for Griffin Armament's M4SD series suppressors, including the M4SD2, M4SDK, 30SD, and 30SDK models. It also works with Griffin's QD Blast Shield. It is not a universal flash hider; compatibility is limited to these Griffin products.

Can I pin and weld this flash hider to a short barrel?

Yes. The M4SD is pre-drilled for pinning and welding and can be permanently mounted to a 14.5" barrel to achieve a 16" overall length carbine, meeting federal length requirements without NFA registration.

What's included in the box?

The Griffin M4SD 3-Prong Flash Hider includes a shim set for fitment adjustment and an over-travel stop washer.

How do I properly install the over-travel stop washer?

The over-travel stop tab should be positioned at the bottom (6 o'clock position) of the muzzle device to prevent over-rotation when attaching your suppressor.