Spindle lock design aligns the expander spindle to perfectly center itself in the die. Provides tight tolerances. Expander spindle improves alignment and enhances accuracy for smoother operation. A solid, one-piece rod guaranteed not to bend or break.Elliptical expander significantly reduces friction and case neck stretch. Threaded and replaceable. The Built in crimper gives you the option of crimping without an extra crimp die. Sure Lock rings lock the die into position w/precise adjustment. Locking screws stay free from threads. Features wrench flats.