The Aero Precision Adjustable Gas Block allows the user to finely tune their gas system for any application. This is particularly useful for managing excess gas to reduce blowback on suppressed firearms, or competition builds where the shooter is looking to mitigate recoil. Features: Standard low-profile design provides great fit under slim profile free float handguards including the Aero Precision R-ONE and S-ONE handguards Adjustment screw is held in place by a spring and detent, providing repeatable audible "clicks" upon adjustment removing the need for secondary set screws that can come loose under recoil Custom machined stainless-steel adjustment screw provides 15 gas adjustment settings Carbon fouling is channeled to a sacrificial chamber to help prevent carbon locking, as well as provide an access point for solvent in the event carbon locking does occur User-serviceable design allows for service and cleaning of the gas system Specifications: Machined from 4140 steel DLC coated Compatible with barrels utilizing a .750 gas block journal Attaches to barrel via 10-32 x 3/16 knurled set screws Includes: Assembled Adjustable Gas Block One 6" 3/32 adjustment wrench for easy gas block adjustment underneath installed handguard Replacement spring and detent included Please note: Aero Precision does not recommend the use of a red threadlocker on the screw threads. If you decide to use a threadlocker, Aero Precision recommends using the non-permanent variety. DO NOT USE A THREADLOCKER OF ANY KIND ON THE GAS BLOCK ADJUSTMENT SCREW.