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Sigma 170-500mm f/5-6.3 DG RF APO Aspherical Ultra Telephoto Zoom Lens for Minolta and Sony

Product Description :
170-500mm ultra-telephoto zoom lens with f5-63 maximum aperture
Multi-layer lens coating reduces flare and ghosting for optimal color balance
Aspherical lens and 3 special-low-dispersion SLD glass elements
Rear focus systems ensure high performance stability and ease of use
Measures 36 inches in diameter and 91 inches long weighs 474 ounces