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Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens for Canon DSLR Cameras

Product Description :
Ultra telephoto zoom lens fast aperture of F28 at the 500mm and F56 at the 1000mm focal length
Dedicated Attachment ensures autofocusing at the 1000mm focal length
SLD and three ELD glass elements provide high image quality from the maximum large aperture
Supplied with 72mm filter holder at the rear
For Canon digital SLRs