Extend the reach of Canon EF-mount telephoto lenses with this C-AF 2x Teleplus Teleconverter from Viltrox. This 2x teleconverter effectively doubles the focal length of the attached lens while retaining autofocus and communication between the camera and the lens. The teleconverter uses a seven elements, four groups optical design to maintain high sharpness and clarity, and the individual elements have been multi-coated to reduce flare and ghosting. This teleconverter is compatible with most EF-mount lenses with a focal length of 100mm or longer.