The RCBS Auto Primer Feeder helps to speed up the reloading process while at the same time curbing misfires and helping to prevent primer contamination from oily fingers. Primer Capacity: 100Accessories: Large and Small primer tube.Notes:Drops primers one at a time into the Primer Plug and sleeve.Nylon primer pick-up keeps primers from falling out.For use with Rock Chucker II and Reloader Special Presses.Does not work with Rock Chucker Supreme or Partner Presses.