Let the Speed Booster Ultra 0.71x Adapter unlock the full potential of your Canon full-frame Ef-mount lenses when paired with Micro Four Thirds-mount cameras. This high-quality, innovative adapter is designed to enhance your photography by increasing the maximum aperture by 1 stop, thus allowing for faster shutter speeds and superior performance in low-light conditions. The adapter's 0.71x magnification factor effectively reduces the crop factor of Micro Four Thirds cameras from 2.0x to 1.4x, expanding your field of view and enabling a more comprehensive capture of your subject.Crafted with a patented 5-element/4-group optical design that incorporates ultra-high index tantalum-based optical glass by Caldwell Photographic in the Usa, the Speed Booster Ultra ensures exceptional image quality.