This fake flash hider easily attaches to the factory-finished plain muzzle or non-threaded barrel (since the factory also finishes the barrels with threads) of the Smith & Wesson M&P15-22 with two set screws. The size and look is identical to the A2 birdcage flash hider/suppressor. Note: This is NOT a flash hider. The slots do not go through to the bore, so the flash is not hidden