The DAA PRIMER-PRO ships including one Magnetic Collar to be used with your Dillon primer tube.Even though the PRIMER-PRO will fill a tube of primers faster than you can use them, some reloaders will still prefer to pre-fill multiple tubes before they start their reloading session, so they do not have to go back and forth to their PRIMER-PRO unit while reloading. For them, we offer a pack of 4 additional Magnetic Collars, designed for use on Dillon Pickup tubes in conjunction with the PRIMER-PRO primer collator.Set includes 4 polymer collars with secured magnets and set screws.Primer tubes are NOT included.