That's just an example bullet that they stuck in the photo. If you look at the other Hornady expander ball types for other calibers, they use the same photo for all of them. I found the item on Midway by just searching for "carbide expander" rather than putting in a specific manufacturer. Glad I was able to help.
Graf & Sons has the same part for about $2.00 less and I think they pay shipping. I have converted all my RCBS dies to carbide expander balls. Eliminates the need for inside neck lubrication. Although, a quick swipe of a pipe cleaner dipped in powered graphite inside the case neck does help.