Pixco EMF AF Confirm Canon Mount Macro Extension Lens Bellows for Canon EOS 5D Mark III, 5D Mark II, 6D,600D, 550D, etc. The adapter enables camera viewfinder focus confirmation light and confirmation sound when focus is correct. Expandable black bellows without light leaks Tripod mount socket Supports AV and Manual Mode. Exposure aperture data can be recorded in EXIF.