Fits to the front of the EF 200-400mm f/4L IS USM Extender 1.4x IS USM, EF 300mm f/2.8L IS II USM and EF 400mm f/4 DO IS II USM, reducing 'flare' caused by light shining directly on the lens' front element. Compatibility EF 300mm f/2.8L IS II USM EF 400mm f/4 DO IS II USM EF 200400mm f/4L IS USM Extender 1.4x
