The Canon EF-EOS R 0.71x Mount Adapter extends your range of compatible lenses whilst maintaining their original field of view. The adapter attaches EF-mount lenses to RF-mount cine and mirrorless cameras and is intended for bodies featuring a Super35 sensor size. The adapter is equipped with an optical system that increases the effective angle of view by 0.71x, minimising the effects of a full-frame to Super35 crop factor. It additionally increases the maximum aperture by one stop. The adapter works by directly attaching to RF-mount camera bodies, with four screws and a split locking collar offering a more secure attachment.