Build a more reliable firearm with the help of this Aero Precision APRH101204C Low Profile Gas Block .625. Aero Precision machined these AR15 Lower Parts from 4140 hardened steel to ensure they're incredibly durable and long-lasting. This Aero Precision APRH101204C Low Profile Gas Block .625" AR15/AR 308 Black Nitride Gas Block features a low profile design for easier installation and the set screws are steel and include a knurled cup point finish for enhanced grip. Pick up the Aero Precision APRH101204C Low Profile Gas Block .625" AR15/AR 308 Black Nitride Gas Block .625, and make sure you protect your weapon and assist in boosting the performance of your rifle.