The RCBS Carbide Tamper Crimp 3-Die Set was specially designed to help decrease the amount of time and hassle involved in the reloading process by eliminating the need for cleaning your cases before prepping them for reloading.This carbide 3-die set comes in a variety of different sizes to accommodate the most popular cartridge case calibers. Included in the RCBS Carbide Tamper Crimp 3-Die Set are the Sizer Die with decapping unit the Seater Die for seating and crimping your case and the Expander Die to expand and bell the case mouth.