The Metabones 1.26x Expander is a lens adapter that lets you use a Canon EF lens on a Fujifilm G mount GFX camera. The adapter enables the Canon EF lens full frame image circle to cover the Medium format sensor of the Fujifilm GFX. This results in a 0.6 stop aperture decrease for the lens. The Expander supports Phase-Detect autofocus and optical image stabilization (IS). The aperture is controlled by the camera body. The focal length and aperture can be adjusted. Adjustments are stored in EXIF data.