KAK Industry XM177 Features The KAK Industry XM177 Flash Hider is designed to be clone correct for the Colt 649 639 619 and 620 as well as the XM177 177E1 and 177E2 moderators giving retro AR-15 builders an accurate period-correct muzzle device. At 4.678 inches overall length the flash hider adds enough length to a 12.5 inch barrel that when pinned and welded brings the rifle to a legal non-NFA overall length. This makes it a practical option for builders who want the retro look without running afoul of barrel length regulations. The device is heat treated to withstand the temperatures generated by sustained firing. A black phosphate coating finishes the flash hider providing corrosion resistance while matching the dark uniform look expected on a retro-styled build. An integrated grenade ring is built into the design giving the flash hider its distinctive vintage appearance without requiring the installer to source or fit separate parts. The ring s counter bore is also capable of hiding a crush washer though a crush washer is not included with this muzzle device. Threaded 1/2x28 to fit standard 5.56 NATO AR-15 barrels the XM177 Flash Hider is a straightforward addition for builders chasing an authentic retro aesthetic. KAK Industry XM177 Specifications Manufacturer: KAK Industry Model: XM177 Caliber: 5.56 NATO Compatible Hosts: AR-15 Color: Black Finish: Phosphate Overall Length: 4.678 Thread Pattern: 1/2x28 Available At: GrabAGun