Eyecup is mainly used to prevent light from entering the eyecup during long-term B-bulb exposure to take pictures; it can also prevent the eyecup from scratching when the camera is not used;
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Prevent debris from entering the viewfinder when the camera is stored.
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How to use the blindfold?
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Remove the rubber eyecup before use, and then insert the eyecup into the card slot on the outside of the viewfinder.
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Applicable models:
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CANON EOS-1D Mark IV, EOS-1 D Mark III, IDsMarkIII,and 7D
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