A Sheffield utility knife, the Quick Change Lock-Back Utility Knife No. 12119, from Great Neck Saw comes equipped with five replacement blades that are conveniently stored in the handle of the knife. Designed with Sheffield's quick change blade and patented one-handed mechanism, this knife is guaranteed to operate like new for the life of the product. The quick change lock-back utility knife also includes a belt clip and folds to a convenient pocket size. This knife uses standard utility knife blades for easy replacement.