" FPC ASS'Y, MAIN " for Canon EF 100-400mm F/4.5-5.6L IS USM lens, part number: YG2-0370-000. - YG2-0370-000 1x FPC ASS'Y, MAIN. - YA2-3656-259 1x HOLDER, MAIN FPC. Lens main board pulled form lens with defective aperture flex (err01) with mounting screws.
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