The optical fiber double attack allow to puttwo optical fiber wiresin front of thebuilt-in flashof thecameraand be able tousethis technology tohave one or twoartificialexternallight sources.
Using it issimple.Justscrew it to thehousingin the dedicated spacein front of theflashandinsertingthe wires endsinto the holeson the coupling,fixing themwith the provided grainsforeach hole.To useonly oneexternal flashisenoughusedthe capssupplied with the accessoryto darkentheunused hole,soas to avoid unwantedpoints of light.