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CowboyStudio One Way Macro Focusing Rail Slider Macro Bellows for Canon EOS Cameras

For use with Canon mount type lenses
Best for extreme Macro photography with MAX magnify ratio up to 81 31 with 50mm Lens
Bellows extend from 40mm to 150mm with locking thumb screw
Built-in Tripod Socket for seamless sticking
Allows smooth movement for more precise focus