There were three versions of the 500mm lens made, and this being the PQ model makes it a later copy able to work with both 6000 series cameras and also the Hy6/AFi bodies. Zeiss did make a very rare 500mm Tele-APO-tessar version with improved optics, but rumor is that there are only about 100 copies or less made. Compared to that one, this is affordable and also fairly light weight considering its focal length. It's an older Zeiss design, but is a decent performer when stopped down. And when you need the reach, then you need it! Compatible with 1.4x and 2.0x tele-extenders as well. The lens is in very nice condition overall with on rub mark on the barrel only and tested for function. It has a built in tripod mount and sliding lens hood.