Calle Blomdahl

This extension ring enables zoom & manual focus specially designed for Canon EF 16-35mm F2.8L ll USM, Canon EF17-40mm F4L USM, AF-S Nikkor 18-35mm F/3.5-4.5G ED, AF-S Nikkor 16-35mm F/4G ED VR.
* Compatible FC focus gear required for manual focusing (can be used in conjunction with a compatible zoom gear).

 

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 Extension Ring 46 with Focus Knob