FX Impact Slug Tensioned Barrel KitKit Includes: Barrel, Pellet Probe & Shroud Magzine not included. Barrel Rigidity for Slug Shooting of 90+ FPE The advancement of slug shooting and the enhancements to the FX Impact have shooters wanting to use heavier slugs at faster speeds. Higher powers require a more rigid barrel to handle these projectiles additional energy and vibrations. The new FX Tensioned Barrel System adds the firmness needed to let you reach the potential of the FX Impact