After waiting months with no success for delivery of a similar adapter system from a another 3rd-party maker, this spring I purchased the Kolari EF-EOS R Drop-In Filter Mount Adapter For Canon EOS R, with the Clear and CPL drop-in filters (see photos) to use with my Canon R6 and EF lenses. Kolari was able to ship these without delay after my purchase was placed. Having used them now in the field, I am extremely pleased with all three components. They are all durable, of high quality and well-finished. The adapter is weather-sealed, and the two filters snap into it snugly with no wiggle or play. The adapter fits and functions with my R6 as if it were an actual Canon accessory (some shooters with large fingers may find the control wheel of the CPL drop-in to be smallish...for me it has been no problem). The clear filter is just that-a dust protective seal for the side gap when not using a CPL or ND drop-in. I have the 2-10 stop VND on order now to complete my current needs. Kolari offers the adapter and a wide assortment of drop-in filters for very reasonable prices IMHO, especially compared the the pricey Canon items.