Enhance your 1911 Fullsize with the SIG MCX 556 Barrel Gas Block Assembly. Designed as a 16" upgrade this original SIG SAUER component is perfect for replacing your existing barrel. Crafted from high-quality materials the threaded barrel is chambered in .45ACP providing the versatility to attach a suppressor or other muzzle devices. A durable knurled thread cap ensures the muzzle is protected when not in use. Engineered for toughness and longevity this factory replacement barrel undergoes special heat treatment. The package includes a link and pin though some fitment may be required.