I found this on FB Marketplace, anyone know what kind of phosphor this uses? My guess would be Halo.

March 2003 phosphor? 

In all seriousness, probably Halophosphate. But, the best way to find out is to light it up.

I would guess that they are a blend including some triphosphor. These are basically a F40T12/741 and I've seen them labeled as "Cool White Plus" "Contractor's CW" and "Home Light Cool" I assume they labeled them differently depending on where and how they were sold (small hardware stores in 2 or 10 packs, versus electric supply stores in cases of 30.)