The MC-11 Mount Converter enables the use of Sigma EF-mount lenses on Sony E-mount mirrorless camera bodies, and maintains full lens performance, including autofocus and auto-exposure, as well as in-camera correction technologies. An integrated LED can be used to display select Sigma lens compatibility with the adapted camera body, and the adapter also supports in-camera image stabilization. In order to maintain a high degree of image quality, the interior of the adapter is flocked to reduce reflections, and it also retains full Exif data to benefit post-production and file management.

Per Sigma, this Mount Converter/Lens Adapter is compatible with a select number of Sigma's own EF-mount lenses, and may or may not be suitable for use with other manufacturers' EF-mount lenses.