If you think about the various steps that go into making these, the cost of the high strength steel, ball bearings, rubber boots, the cost of engineering, testing, QA...you have to wonder how any of them could be selling for less than $300-$500. And just think of what it would cost to ship a 15 lb axle assembly from China to the US. Even accounting for lower labor costs, it's astonishing that they can be this cheap.