Smply thread a HornadyA(R) Lock-N-LoadA(R) Conversion Kit into your RCBSA(R) Rock Chucker or other reloading press using a 1A 1/4"-12 thread and you're ready to start using the Lock-N-LoadA(R) System.It's the easiest way to get the most out of your reloading press. These bushings let you take advantage of Hornady'sA(R) Lock-N-LoadA(R) technology even if you own a competitors reloading press.