This lens hood is designed specifically to fit the Canon EF 400mm f/2.8L IS III USM. It prevents stray light from entering the lens which can be a source of flare and ghosting and also provides a degree of protection for the lenss front element. Its built to the same exacting standards as the 400mm f/2.8L IS III USM, designed to blend in perfectly with the lenss thermally insulating white paint exterior.BenefitsPrevents flare and ghosting when shooting into the lightProtects the lens front element from accidental damageDesigned specifically for the EF 400mm f/2.8L IS III USMStyled to match the white exterior of Canons super-telephoto lensesLightweight, weighing just 270g (approx.)Can be reversed and attached to the lens to save spaceThis lens hood is designed specifically to fit the Canon EF 400mm f/2.8L IS III USM. It prevents stray light from entering the lens which can be a source of flare and ghosting and also provides a degree of protection for the lenss front element. Its bui