Opteka ET-67 Lens Hood for Canon EOS EF 100mm f/2.8 Macro USM Lens. Opteka's ET-74 Lens Hood is designed for Canon EF 70-200mm f/4L IS USM and EF 70-200mm f/4L USM Digital SLR Lens. Lens hoods are primarily designed to prevent unwanted stray light from entering the lens by extending and shading the end of the lens.
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