This converter is peak, can be konnektieren well, has hardly play, and makes a robust impression. It brings the object (use it mostly on macro lens), fairly close up. Unfortunately, the combination is with my lenses but without autofocus possible, however, mostly used in macro photography, or as in my 500 telephoto lens to manual focus anyway. Although he is not cheap, but quality has its price now. Nevertheless, it is an acceptable variant for expensive Macro or telephoto lenses, especially as it required only once. Who is necessarily fixed to the autofocus, should then take the smaller converters Sigma 1.4, which is often used with AF. Conclusion: Cheap, acceptable solution, compared to expensive, long lenses. For me, the acquisition was worth.