its the plastic primer holder/dispenser used in the video above
The "plastic primer holder/dispenser" does not come with the Lee Load-All II and is not needed.
I think you need to read the manual of your Lee Load-All II.
Again the Lee Load-All II comes with everything to prime and de-prime hulls.
https://media.mwstatic.com/productdocuments/owners manual/436/436640.pdf



















































