This comes from the AE site:

"The blue 7075 T-6 aluminum rear hubs are all new, with a single-clamp style left hub, and a dual-bearing supported right diff hub featuring the large "D" style locking diff rings (allowing the greater diameter ball pattern) as preferred by most of our Team drivers. The graphite-thru, Pro-style rear axle is from IRS."

If you ask me, the graphite axle is from IRS and the hubs are made by AE themself.