Our Low proflie Stainless Steel Clamp On micro gas block is CNC precision machined with superior quality steel. It is Heat treated and Erosion resistant. This Low Pro Micro gas block replaces the existing A2 front sight, and is sleek and small to allow a longer rail to be placed over. Can be used when installing a Mid Length, Specter Length or Rifle Length hand guard to a shorter length gas system barrel. It is compatible with 5.56/.223 with a .750 diameter barrel. Roll pin & set screws are included. No modification to your barrel is required.