Of all the AR15 platform modifications available, an quality Clamp-on Gas Block from Alien Armory Tactical is among the most pivotal AR-15 / M4 Accessories you can buy when it comes to performance enhancement. A firm AR Gas Block will all but eliminate your gun’s recoil, making for a seamless recoil recovery and a quicker target acquisition in follow-up shots. It will also prevent the bolt from overheating, rendering your cool down period unnecessary. In the name of reliability, most AR manufacturers err on the side of over-gassing the operating system of the upper receiver, making the stock AR a bit of a beater rifle with a snappy recoil. The Clamp-on Gas Block from Alien Armory will fine-tune the gas pressure on the standard, over-gassed direct impingement AR15 systems by sealing the gap between the gas tube and the gas port.