The RCBS Rock Chucker Supreme Auto Priming Unit transforms your reloading setup by converting one-at-a-time priming into an efficient tube-fed priming system that eliminates direct primer handling.RCBS Rock Chucker Supreme Auto Priming UnitConverts manual priming to automated tube-fed systemEliminates direct handling of primers for safer operationAttaches to same mount point as standard priming armCompatible with Rock Chucker Supreme pressPerfect for reloaders seeking to increase efficiency and safety in their ammunition preparation process while maintaining the precision and reliability RCBS is known for.