The RCBS AmmoMaster .50 BMG Press Conversion Kit was specifically designed for use with the RCBS AmmoMaster to convert it for use with .50 Browning Machine Gun (BMG) cartridge cases. If you are a serious reloader who prefers .50 BMG cases, this press conversion kit is a must-have. Included in the RCBS AmmoMaster .50 BMG Press Conversion Kit is everything you need to convert your standard AmmoMaster for use with .50 BMG cases. This kit includes all of the parts you need to adapt your press to the 1 _-inch die size for use with .50 BMG cases.