Quick Overview Extending the range of compatible lenses, the Canon Control Ring Mount Adapter EF-EOS R is a unique lens adapter designed for attaching any EF or EF-S-mount lens to the EOS R mirrorless digital camera. This sophisticated adapter incorporates a customizable Control Ring, the same as that on native RF-mount lenses, for intuitively adjusting exposure settings, such as ISO, aperture, and exposure compensation. This ring provides tactile feedback when being turned, making it easy to recognize and control your settings adjustments. It also retains full autofocus and image stabilization capabilities and contains no optical components, thereby maintaining the original optical quality of the mounted lens. Additionally, it is dust- and water-resistant, making it suitable for use in harsh weather conditions.