You will need the “push through sizing die body” and a nose bushing that installs into the die body. Also you will need a bottom punch which is caliber specific for the bullet you are sizing.It is what pushes the bullet up into the die. It fits into the slot in the ram of the loading press. This is installed into your reloading press and only sizes the nose portion of the bullet. It is then driven back down out of the die body. It does not go into the die far enough to size the whole bullet. It then can be sized in your regular bullet sizer. Hopes this helps. It comes with pictures and a “how to” explanation.