Shop › AERO ADJ LOW PROFILE GAS BLOCK .625 AERO ADJ LOW PROFILE GAS BLOCK .625 $71.99 Aero Precision Low Profile Adjustable Gas Block, Fits AR15 with 0.625" Barrel, Nitride Finish, Black APRH101613C Quantity: Add To Cart Added! Aero Precision Low Profile Adjustable Gas Block, Fits AR15 with 0.625" Barrel, Nitride Finish, Black APRH101613C