They are a different hardness than the stock steel shafts, and are ductile in a different way. They are much harder to snap in half or to break the ears that hold the universal joint.
Alloy USA shafts are made in India, I think. Not the best, but still a huge upgrade from stock.
Please note that it could just be that single outer stub axle. You have four shafts on the front axle, the long inner on the passenger side, the short inner on the driver side, and the two stubs that connect to the wheels via a universal joint. The Alloy USA shafts are anodized black, the stock steel ones are bare, gray-silver steel - or perhaps brown with rust, heh, heh, heh...
You have to remove them partially to see what you actually have.
Lucky you! I just paid nearly $600 for a set of these!
Here is the home page with the ad blurb to explain it to you. Remember, these guys are selling you something, but it happens to be a genuinely good product in this case.