The NcSTAR AR-15 Hand Guard Weaver Style Rail is designed for use with AR-15 Rifles. It is made of aluminum. Weaver style base allows for mounting tactical accessories like flashlights, lasers, grips, scopes, holo sights and red dots. It is easy to install, no gunsmith installation required; requires removing your hand guard, then using the provided screws. The rails are bolted on through the ventilation holes on the upper or lower side of the hand guard. The bolts are recessed so it will not interfere with the barrel of your rifle.