Anybody seen this type of gt500 Overdrive pulley?

[Regulars520]

Has anybody here seen this type of gt500 overdrive pulley from steeda before? I have not had my stock pulleys off so Im looking at this and looking at the stock pulley and scratching my head. Is the stock pulley a 2 piece pulley?

 

[Speedboosted]

That looks like a 6 rib pulley to me, so accessory belt. Not sure what the purpose of that is.

 

[Regulars520]

Its actually a 10 rib here is a side shot

 

[Regulars520]

Found out what it is. Its not an overdrive pulley. It is part of this kit.
http://www.jpcracing.com/steedas-10rib-belt-drive-system-for-05-10-mustang-w-whipple/