RCBS Carbide 3-Die Set for.45 Long Colt is made from polished and heat-treated steel, the RCBS Carbide 3-Die Set has a Sizer Die with Decapping Unit, Expander Die for expanding and belling the case mouth and a Seater Die for seating and crimping the bullet (Straight wall cases will roll crimp, unless the description indicates it has a taper crimp). No sizing lube is needed with these carbide dies.