Meike releases Drop-in Filters for the Canon EF-EOS R adapter - Newsshooter
Gear of the Year: Gannon's choice - Kolari EF-RF Drop-In Filter Mount Adapter: Digital Photography Review
Amazon.com : NEEWER EF to EOS R Mount Adapter with Drop in Variable ND Filter ND3-ND500, Autofocus Lens Converter Ring Compatible with Canon EF/EF-S Lens to EOS R EOS RP EOS R5
5 Favorite Features Of Canon's EOS R System - Page 3 of 5 - Outdoor Photographer
Meike MK-EFTR-C – EF/EF-S to EOS-R Drop-in VND Filter Adapter Announced | CineD
Kolari R Drop-in Filter Set for EF-EOS R Lens Adapter – Kolari Vision
Canon Drop-in Filter Mount Adapter EF-EOS R with Drop-in Variable ND Filter A
Drop in Filter Mount Adapter EF-EOS R | Canon Australia