The 4-stop Kolari Vision IRND Drop-In Filter is compatible with the EF to EOS R drop-in filter adapter from Kolari or Canon. The frame is aluminum and the optics are an ultra-strong Gorilla Glass substrate with AR/AS coatings for increased transmission, reduced reflections, and easy cleaning. The filter has a wide grip and offers a lanyard attachment point for your convenience. It s thickness-matched to minimize focus shift.