FAIR / This is a USED lens. There is some debris on the inside of the lens, but is is minor. The casing shows signs of use and age. Small marks on the front of the lens. The mount is bent, please see photos, however it looks like it could be repaired.
Zeiss Ikon engaged Carl Zeiss Oberkochen to develop the best lenses available for a 35mm camera system. The result was the complete line of the Contarex lenses. Carl Zeiss did not develop a completely new line of optics from scratch but used instead design elements from the Contax line especially for the medium to long tele lenses. Because of the very special lens mount and diaphragm transfer mechanism the Contarex lenses are incompatible to any other camera system!
The quality of the lenses was probably one of the main reasons for many customers to buy a Contarex camera. The 50mm f2 Planar for example, is probably one of the best standard lens ever made!