In addition to all the features of our Carbide 3 Die Sets, the premium Carbide 4 Die Sets also include a separate taper crimp die. The 4 Die Set is perfect for those loading pistol calibers that headspace on the case mouth. Whether you are reloading your 9mm Luger or your .357 S&W Magnum - Shop Lyman for our Premium Carbide 4 Die Sets!