This Alexander Arms 6.5 Grendel kit is fully-inspected by Alexander Arms for proper critical dimensions. This product carries the standard one-year limited warranty against factory defects of the parts being sold. Warranty does not cover the final functionality of the rifle built with this kit. Because of the advanced nature of firearms assembly and the possibility of physical harm to a user, it is expected that the assembler of this kit has adequate technical knowledge of firearms assembly. All of the barrels offered as individuals or in kits are the same barrels used in Alexander Arms factory builds.