Canon Drop-In Clear Filter ACanon Drop In Clear Filter A A drop in filter designed to be used with the Canon Drop In Filter Mount Adapter EF EOS R. Use this filter when no other filter effects are desired as the clear glass helps protect the interior of your camera body and the rear element of the lens while the Drop In Filter Mount Adapter EF EOS R is in use. Key Features: A drop in filter to fit the Filter Mount Adapter with clear glass for when no filter effect is desired