The Canon EF-EOS R Drop-in Filter Mount Adapter facilitates the addition of creative filters when using EF or EF-S lenses with EOS R mirrorless cameras. A circular polarizer filter is provided with the adapter. Its unique mechanism allows you to use drop-in polarizer and ND filters. The adapter also ensures full electronic communication between the camera and lens to employ autofocus and image stabilization. There are no optical elements in the adapter to keep the original optical quality intact.