(Compatible: Canon EF-S 55-250mm IS STM f/4.5-5.6 lens. 1) This lens mount is for EF-S 55-250mm lens to EF mount modification. Canon EF-S 55-250mm To EF Lens Mount. 1x EF lens mount only. 3) As you can see a hole on the mount, it's because EF-S 55-250mm lens has two versions, one version has an ultrasonic motor shaft that is raised out from the mount.
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