Surefire 4-Prong flash hider - fast attach 215A 

the original 4-prong flash hider

model FH556-215A

The FH556-215A is a high-performance flash hider for the Colt Commando, M4, M16, HK416, and to other 5.56 mm semi-auto, bolt-action, or assault rifles with Mil-Spec 1/2-28 muzzle threads. It also serves as a precision, rock-solid adapter mount that enables rapid no-tools attachment of SureFire FA556K, FA556-212, FA556MG, or MINI suppressors to these rifles or to other rifles with the same muzzle thread/configuration.

The end of this adapter has 4 open prongs.  This is the originial Surefire 4-prong, and its larger cousin is found on the British L129A and the HK 417 rifles in 7.62mm NATO.

SureFire flash hiders deliver superior muzzle flash suppression. This provides three benefits—minimizing degradation of your night-adapted vision, helping to conceal your position, and reducing muzzle rise. Machined from heat-treated stainless steel, finished in a tough, corrosion-resistant coating, all SureFire flash hiders are extremely resistant to gas and particle erosion and will perform perfectly for thousands of rounds.

NOTE: This SureFire flash hider also serve as adapter mounts for our Fast-Attach® sound suppressors. If you do not plan to attach a SureFire sound suppressor to your firearm, we recommend choosing a shorter-length muzzle brake or flash hider. SureFire muzzle brakes and flash hiders that mate with our overlap suppressor models are longer in order to extend rearward over the barrel, a feature that is unnecessary unless mounting an overlap suppressor.

The Fast Attach family of Suppressors and muzzle devices predate the SOCOM series, and while the flash hider looks similar, this flash hider is not be used with the SOCOM RC / RC2 familiy of suppressors.  The SOCOM series of Surefire suppressors will actually seem to fit, but will not lock in place and presents a danger when shooting, and should not be used.

Features

• Provides rock-solid suppressor attachment in seconds without tools
• Precise tolerances provide minimal and consistent zero shift regardless of number of attach/detach cycles
• Acts as high-efficiency flash hider when suppressor is removed
• Extreme resistance to heat and gas/particle erosion
• Installation requires no permanent modifications to most weapons

Package includes:

• Surefire 4-prong Fast Attach flash hider
• a variety of shims
• small container of Rocksett (this could dry-up over time, and need to be replaced)
• no wrench is included
• may ship in retail pack, or in small plastic bag (occaisionally we need to remove retail packaging to save on space in our storage bins)

Charlie's recommends installation by a gunsmith or qualified armorer.  While this can be a DIY project, it is important to get the timing correct and also to apply the correct Rockset to assure your mount does not cause damage to your suppressor.