EF to RF drop in filter by LATCHE for Canon EOS RF Camera. Pick up one of these Drop in Filters for Canon's EF to RF adapter.  This filter contains no glass and is not threaded, so it serves to close the opening on the side of the adapter.

Please not this is a product that has been 3d printed, so refer to photos for quality.

Why have another piece of glass? And why drop a couple of F-stops. Designed in the UK. Take a look at the instagram and find us at: @latche_uk