The item is described as internally focusing and that the lens doesn't extend when focusing, that's not correct. The lens literally doubles in size when focused right out. Also I have no idea why there's an AF in its name, its not on the box or in anything else I can find.
One good thing though is that it is very very sharp!
Its built solid, focus is ultra fast, the VR really works great. But if your serious about your photography give this a miss as the image quality is no where near good enough, if you just want a lens to mess about with you may be happy with it.