Need help identifying an item

[bender152]

A while back, I bought a used Dillon 550 package here on the boards. The seller included a bunch of extra items. I've figured out what everything else is, but I'm stumped about the item circled in the pic below.

I've included the standard primer slide for a size comparison.

Could anyone clue me in as to what this is? The short slide as well as the two items below it were all in the same bag.

Thanks in advance.

[XDRoX]

Looks like a square deal primer slide to me.

http://www.dillonprecision.com/uimages//SDB_Pg_4_m.jpg

[bender152]

Looks like a square deal primer slide to me.
http://www.dillonprecision.com/uimages//SDB_Pg_4_m.jpg

Ahh.. that would explain why I couldn't find it in the list of parts for the 550.

Thanks for your help.

[Revoman]

"Looks like a square deal primer slide to me.
http://www.dillonprecision.com/uimages//SDB_Pg_4_m.jpg"

Confirmed, it also looks like it is an newer one, they changed the 'wheel' part. Can't quite tell if it's a large or small cup though.